12-Letter Words Starting with I

All 326 twelve-letter words that start with I

IC

• ichthyofauna26n. The fish of a particular region.
• iconoclastic18adj. Characterized by attack on established and accepted beliefs, customs...
• iconographer20n. One who creates (religious) icons.
• iconographic22adj. Of or pertaining to iconography.

ID

• idealization22n. The act or process of idealizing.
• identifiable18adj. Capable of being distinguished and named.
• identifiably21adv. In a manner or state that is capable of being distinguished or named.
• identitarian13adj. Based on a notion of group identity; relating to the ideology of...
• idiosyncrasy21n. A behavior or way of thinking that is characteristic of a person or a...

IL

• illegibility18n. The characteristic or quality of being illegible; the quality of being...
• illegitimacy20n. The state of being illegitimate.
• illegitimate15adj. Not conforming to known principles, or established or accepted rules or...
• illiberalism16n. The principle, state or quality of being illiberal.
• illogicality18n. Something illogical.
• illuminating15adj. Providing illumination or light.
• illumination14n. The act of illuminating, or supplying with light; the state of being...
• illuminative17adj. Of, capable of, or causing illumination.
• illustration12n. The act of illustrating; the act of making clear and distinct.
• illustrative15adj. Demonstrative, exemplative, showing an example or demonstrating.

IM

• imidacloprid20n. The very widely used neonicotinoid insecticide...
• immaculately21adv. In an immaculate manner; in a manner free of stain or blemish; without...
• immeasurable18adj. Impossible to measure.
• immeasurably21adv. In a manner that is not measurable, in a way that cannot be measured.
• immemorially21adv. In an immemorial manner, from time immemorial.
• immiseration16n. Synonym of immiserization (“the process of making miserable or poor...
• immoderately20adv. In an immoderate manner.
• immunisation16n. The process of immunising signalling and traction power supplies so...
• immunization25n. The process by which a person is safely exposed in a controlled manner...
• immunologist17n. A person who studies or practices medicine in the area of immunology.
• immutability21n. The state or quality of being immutable; immutableness.
• impartiality19n. The quality of being impartial; fairness.
• impenetrable18adj. Not penetrable.
• impenetrably21adv. In an impenetrable manner or state; imperviously.
• imperatively22adv. In an imperative manner.
• imperfection21n. Those qualities or features that are imperfect; the characteristic...
• imperfective24adj. Of, relating to or having the properties of the imperfective aspect.
• imperishable21adj. Not perishable; not subject to decay; enduring permanently.
• impermanence20n. Lack of permanence or continued duration.
• impersonally19adv. In an impersonal manner.
• impersonator16n. One who fraudulently impersonates another person.
• impertinence18n. Lack of pertinence; irrelevance.
• implantation16n. The way in which an organ, bone, muscle etc. becomes inserted into its...
• implantology20n. The science of or techniques involved in dental implants.
• impoliteness16n. The state of being impolite; incivility; rudeness.
• imponderable19adj. Not ponderable; without sensible or appreciable weight; incapable of...
• impoverished23adj. Reduced to poverty.
• impregnation17n. The act of making pregnant; fertilization.
• impressively22adv. In an impressive manner; forcibly.
• imprisonable18adj. Capable of being imprisoned.
• imprisonment18n. A confinement in a place, especially a prison or a jail, especially as...
• improvidence22n. The quality of being improvident; want of foresight or thrift.

IN

• inaccessible18adj. Not able to be accessed; out of reach; inconvenient.
• inaccurately19adv. In an inaccurate manner; incorrectly; inexactly.
• inactivation17n. The process of rendering something inactive.
• inadequately25adv. In an inadequate manner.
• inadmissible17adj. That cannot be admitted as evidence at a trial.
• inadvertence18n. The state or quality of being inadvertent; inadvertency; heedlessness...
• inapplicable20adj. Not applicable; that does not apply or cannot be applied; unsuitable or...
• inarticulate14adj. Not articulated in normal words.
• inauguration13n. The act of inaugurating, or inducting into office with solemnity...
• inauspicious16adj. Not auspicious; ill-omened.
• incalculable18adj. Impossible to calculate.
• incalculably21adv. In an incalculable manner.
• incandescent17adj. Emitting light as a result of being heated.
• incapability21n. The condition of being incapable.
• incapacitate18v. To make someone or something incapable of doing something; to disable.
• incarcerated17adj. Imprisoned.
• incautiously17adv. In an incautious manner; with a lack of caution.
• incestuously17adv. In an incestuous manner.
• incidentally18adv. By happenstance; in a particular case which has little to no bearing...
• incineration14n. The act of incinerating, or the state of being incinerated; cremation.
• incisiveness17n. The quality or state of being incisive; incisivity.
• inclinometer16n. An instrument that displays the angle of an aircraft relative to the...
• inclusionary17adj. Marked by inclusiveness.
• incoherently20adv. In an incoherent manner.
• incomparable20adj. Not comparable.
• incomparably23adv. In an incomparable manner.
• incompatible20adj. Of two or more things: that cannot coexist; not congruous because of...
• incompetence20n. An inability to perform; a lack of competence; ineptitude.
• incompetency23n. The condition of being incompetent.
• incompletely21adv. In an incomplete manner.
• incompletion18n. The state or quality of not being complete.
• inconclusive19adj. Not conclusive, not leading to a conclusion.
• incongruence17n. An absence of congruence.
• inconsistent14adj. Not compatible (with another thing); incompatible, discrepant, at odds.
• inconsolable16adj. Not consolable; unable to be consoled or comforted, usually due to...
• inconsolably19adv. In an inconsolable manner.
• incontinence16n. Lack of self-restraint, an inability to control oneself; unchastity.
• inconvenient17adj. Not convenient.
• incorporated17adj. Being a type of company, a legal entity where the ownership has been...
• incorporator16n. One who, or that which, incorporates.
• incorrigible17adj. Defective and impossible to materially correct or set aright.
• incorrigibly20adv. In an incorrigible manner.
• incorruption16n. The state of being incorrupt.
• increasingly18adv. Increasing in amount or intensity.
• incrustation14n. The act of incrusting, or the state of being incrusted.
• indebtedness16n. State of owing money; being in debt.
• indecisively21adv. In an indecisive manner.
• indeclinable17adj. That one cannot decline; unavoidable.
• indefeasible18adj. Not liable to being annulled or declared void.
• indefensible18adj. Not defensible; not capable of being defended.
• indefensibly21adv. In an indefensible manner.
• indefinitely19adv. In a manner that is not definite.
• indelicately18adv. In an indelicate manner.
• independence18n. The quality or state of being independent; lack of dependence; the...
• independency21n. An independent territory or state.
• indexicality25n. The quality or state of being indexical.
• indifference21n. The state of being indifferent.
• indigenously17adv. In an indigenous way.
• indigestible16adj. Difficult or impossible to digest.
• indirectness15n. The condition of being indirect.
• indiscipline17n. Lack of discipline.
• indiscreetly18adv. In an indiscreet manner.
• indiscretion15n. The quality or state of being indiscreet; lack of discretion.
• indisputable17adj. Not disputable; not open to question; obviously true.
• indisputably20adv. In a manner that is incapable of being disputed or argued against.
• indissoluble15adj. Lasting; indestructible; not possible to dissolve, disintegrate or...
• indissolubly18adv. In an indissoluble manner; in a manner that is unable to be dissolved.
• indistinctly18adv. In an indistinct manner.
• individually20adv. As individuals, separately, independently.
• indoctrinate15v. To teach (a person) with a biased, one-sided or uncritical ideology; to...
• industrially16adv. Concerning industry.
• industrywide20adj. Extending throughout a particular industry.
• ineffability23n. The quality or state of being ineffable.
• inefficiency25n. Lack of efficiency or effectiveness.
• inelasticity17n. The quality of being inflexible.
• inequivalent24adj. Not equivalent.
• ineradicable17adj. Not able to be eradicated; (of a root, plant, etc.) too deep to remove.
• inexactitude22n. A lack of exactness; something inexact or imprecise.
• inexperience23n. A lack of experience.
• inexplicable25adj. Impossible to explain; not easily accounted for.
• inexplicably28adv. In an inexplicable manner; for an unknown reason.
• inexpressive24adj. Lacking expression or emotion.
• inextricable23adj. Impossible to untie or disentangle.
• inextricably26adv. In an inextricable manner.
• infanticidal18adj. Of or pertaining to infanticide.
• infectiously20adv. In an infectious manner.
• infelicitous17adj. Unhappy or unfortunate.
• infibulation17n. An act of fastening.
• infiltration15n. The act or process of infiltrating, as of water into a porous...
• infiltrative18adj. That infiltrates.
• inflammasome21n. A multi-protein complex that is responsible for inflammatory rheumatic...
• inflammation19n. The state of being inflamed.
• inflammatory22adj. Tending to inflame or provoke somebody.
• inflationary18adj. Causing or liable to cause inflation.
• inflectional17adj. Of or pertaining to inflection.
• infographics23n. The visual representation of data.
• infotainment17n. A form of programming (cinematic, television, live action, etc.) that...
• inframammary24adj. Below the breast.
• infraorbital17adj. Below the orbit of the eye.
• infrequently27adv. Not frequently.
• infringement18n. A violation or breach, as of a law.
• infundibular18adj. Having the shape of a funnel.
• infundibulum20n. A funnel-shaped cavity or organ.
• ingloriously16adv. In an inglorious manner.
• ingratiating14adj. Which ingratiates; which attempts to bring oneself into the favour of...
• ingratiation13n. The state of being ingratiating.
• inhabitation17n. The act of inhabiting, or the state of being inhabited; indwelling.
• inhalational15adj. Administered as a gas or vapour that is inhaled.
• inharmonious17adj. Not in harmony.
• inhospitable19adj. Not inclined to hospitality; unfriendly.
• innovational15adj. Of or pertaining to innovation.
• innovatively21adv. In an innovative manner.
• inordinately16adv. In an inordinate manner.
• insalubrious14adj. Unhealthful, not providing or promoting health.
• insecticidal17adj. Of, relating to, or being insecticide; insect-killing.
• insemination14n. A sowing of seed; the act of inseminating.
• insightfully22adv. In an insightful manner; with insight.
• insolubility17n. The quality of being insoluble.
• inspectional16adj. Of or pertaining to an inspection.
• inspectorate16n. An organized group of inspectors.
• installation12n. An act of installing.
• instauration12n. A restoration after decay or dilapidation; a renewal; a repair.
• instillation12n. The act of instilling.
• instructable16adj. Capable of being instructed; receptive to instruction or education.
• instructress14n. A female instructor.
• instrumental14adj. Essential or central; of great importance or relevance.
• insufferable20adj. Not sufferable; very difficult or impossible to endure; intolerable...
• insufferably23adv. In an insufferable manner.
• insufficient20det. An inadequate quantity of; not enough.
• insufflation18n. The action of breathing or blowing into or on.
• insurability17n. The quality of being insurable.
• insurrection14n. The action of part or all of a national population violently rising up...
• intellection14n. The mental activity or process of grasping with the intellect...
• intellectual14adj. Pertaining to, or performed by, the intellect; mental or cognitive.
• intelligence15n. The capacity of mind, especially to understand principles, truths...
• intelligible15adj. Capable of being understood; clear to the mind.
• intelligibly18adv. In an intelligible manner.
• intemperance18n. Lack of moderation or temperance; excess.
• intensifying19n. An intensification.
• interborough18adj. Between boroughs.
• intercalated15adj. Interleaved, formed in distinctly alternating layers.
• interception16n. An act of intercepting something, the state of being intercepted, or a...
• intercession14n. The act of intervening or mediating between two parties.
• intercessory17adj. Of or pertaining to intercession.
• intercoastal14adj. From one coast to another.
• intercompany21adj. Between, or involving, different companies.
• interconnect16v. To connect to one another.
• intercountry17adj. Between countries.
• intercutting15n. An act or instance of something being intercut.
• interdiction15n. The act of interdicting or something interdicted.
• interdigital14adj. Between the fingers or toes.
• interference17n. The act of interfering with something, or something that interferes.
• intergeneric15adj. Between organisms of different genera.
• interglacial15adj. Occurring between glaciations (colloquially known as ice ages).
• interjection21n. An exclamation or filled pause; a word or phrase with no particular...
• interlaminar14adj. Occurring between layers.
• interleaving16n. The action of interleaving.
• interlibrary17adj. Between libraries.
• interlingual13adj. Spanning multiple languages; having a multilingual flair or quality.
• interlinking17adj. Linked or locked closely together as by dovetailing.
• interlobular14adj. Between lobules.
• interlocking19adj. Linked, locked, or fitted closely together.
• interlocutor14n. A person who takes part in dialogue or conversation: a locutive partner.
• intermediacy20n. The condition of being intermediate.
• intermediary18adj. That intermediates.
• intermediate15adj. Being between two extremes, or in the middle of a range.
• intermeshing18adj. That mesh between one another.
• interminable16adj. Existing or occurring without interruption or end; ceaseless, unending.
• interminably19adv. In an interminable manner; (seemingly) endlessly.
• intermission14n. A break, especially between two performances or sessions, such as at a...
• intermittent14adj. Stopping and starting, occurring, or presenting at intervals; coming...
• intermixture21n. A mass formed by mixture; a mass of ingredients mixed.
• intermontane14adj. Between mountains.
• internalized22adj. Of discriminatory views: held against one's own group, as a result of...
• internetwork19n. A network of networks.
• internuclear14adj. Acting between nuclei.
• interoceanic16adj. Between oceans; connecting two oceans.
• interoperate14v. To work reliably with another system.
• interorbital14adj. Between orbitals.
• interosseous12adj. Between bones.
• interpleader15n. One who makes an interplea.
• interpolator14n. One who, or that which, interpolates.
• interpretant14n. The effect of a sign on someone who reads or comprehends it.
• interpreting15n. Synonym of interpretation (an act of interpreting or explaining what is...
• interprocess16adj. Between processes.
• interrelated13adj. Having a mutual or reciprocal relation or parallelism; correlative.
• interrogator13n. One who interrogates; a person who asks questions, especially one who...
• interruption14n. The act of interrupting, or the state of being interrupted.
• interruptive17adj. Acting or tending to interrupt.
• interscience16adj. Between sciences.
• intersection14n. The junction of two (or more) paths, streets, highways, or other...
• interservice17adj. Involving relationships between branches of the armed forces.
• intersession12adj. Between sessions.
• interspecies16adj. Occurring or arising between species; interspecific.
• interspersed15adj. Placed at intervals amongst other things.
• interstadial13adj. Between developmental stages.
• interstellar12adj. Between the stars.
• interstitial12adj. Of, relating to, or situated in an interstice.
• interstitium14n. An interstitial space within a tissue or organ.
• intersubband17adj. Between subbands.
• intertextual19adj. Pertaining to intertextuality; being or involving the reference to one...
• intertwining16n. The pattern or motion of something that intertwines.
• intervarsity18adj. Taking place between universities.
• intervention15n. The action of intervening; interfering in some course of events.
• intervocalic19adj. Existing or occurring between vowels.
• interweaving19n. The motion or position of things that interweave; an elaborate tangle.
• interworking20n. Interoperability.
• intimidating16adj. Threatening, producing feelings of fear or timidity.
• intimidation15n. The act of making timid or fearful or of deterring by threats; the...
• intimidatory18adj. That intimidates; intimidating.
• intonational12adj. Pertaining to intonation.
• intoxicating22adj. Able to intoxicate; an intoxicant.
• intoxication21n. A poisoning, as by a spirituous or a narcotic substance.
• intracardiac17adj. Inside the heart.
• intracoastal14adj. Within or near a coast.
• intracranial14adj. Of or pertaining to the brain or inside of the head; within the cranium.
• intragastric15adj. Within the stomach.
• intrahepatic19adj. Within the liver.
• intraluminal14adj. Within a lumen.
• intranasally15adv. Within, or into, the nose.
• intransigent13adj. Unwilling to compromise or moderate a position; unreasonable; stubborn.
• intransitive15adj. Not transitive: not having, or not taking, a direct object.
• intranuclear14adj. Within a nucleus.
• intraosseous12adj. Within a bone.
• intrapreneur14n. A person employed to work independently within a company in order to...
• intrapsychic24adj. Within the psyche or mind.
• intraspecies16adj. Between or among members of a single (taxonomical) species; within a...
• intratumoral14adj. Within a tumor.
• intrauterine12adj. Located or taking place inside the uterus.
• intravesical17adj. Within the urinary bladder.
• intravitreal15adj. Within an eye.
• intriguingly17adv. In an intriguing manner; with intrigue; with artifice or secret...
• introduction15n. The act or process of introducing.
• introductory18adj. Introducing; giving a preview, idea or foretaste of.
• introjection21n. The process whereby the ideas of another are unconsciously incorporated...
• intromission14n. The state of being allowed to enter; admittance.
• intromittent14adj. Conveying, sending or passing into a body.
• introversion15n. A turning inward, particularly.
• intuitionism14n. An approach to mathematics/logic which avoids proof by contradiction...
• intuitionist12n. A person who studies intuitionistic mathematics.
• invalidation16n. The act of invalidating, or the state of being invalidated.
• invasiveness18n. The quality of being invasive.
• invertebrate17n. An animal without vertebrae (i.e., without a backbone).
• investigator16n. One who investigates.
• invigorating17adj. Giving strength, energy and vitality; quickening; stimulating.
• invigoration16n. The act of invigorating or the state of being invigorated.
• invisibility20n. The state of being invisible.
• invitational15adj. Serving as an invitation; inviting.
• invulnerable17adj. Incapable of being injured; not vulnerable.

IR

• irascibility19n. The quality of being irascible; irritability of temper.
• irrationally15adv. In an irrational manner; without reason; in a manner contrary to reason.
• irredeemable17adj. Not redeemable; not able to be restored, recovered, revoked, or escaped.
• irredeemably20adv. In an irredeemable manner; beyond redemption.
• irregularity16n. An instance of being irregular.
• irrelevantly18adv. In an irrelevant manner.
• irremediable17adj. Unable to be remedied, cured, corrected or repaired; irreparable...
• irremediably20adv. In a manner, or to a degree, that precludes remedy, cure, or...
• irresistible14adj. Impossible to resist.
• irresistibly17adv. In an irresistible manner.
• irresolution12n. Lack of resolution; lack of decision or purpose; vacillation.
• irresolvable17adj. Impossible to resolve; insoluble.
• irrespective19adj. Heedless, regardless.
• irreverently18adv. In an irreverent manner.
• irreversible17adj. Incapable of being reversed or turned about or back; incapable of being...
• irreversibly20adv. In an irreversible manner.
• irritability17n. The state or quality of being irritable; quick excitability.
• irritatingly16adv. In an irritating way; in a manner causing irritation, or that irritates.
• irrotational12adj. Not rotating or not pertaining to rotation.

IS

• isolationism14n. A national (or group) policy of non-interaction with other nations (or...
• isolationist12adj. Relating to, or supporting, isolationism.
• isoquinoline21n. An isomer of quinoline, many of whose derivatives occur as alkaloids...
• isothermally20adv. In an isothermal manner; at constant temperature.
• isotopically19adv. With regard to isotopes.
• isotretinoin12n. A cis isomer of retinoic acid that is a synthetic derivative of vitamin...

IT

• itraconazole23n. A particular triazole antifungal agent (trademark Sporanox) that may be...

Questions about these words

How many twelve-letter words that start with I are there?

Word.ws lists 326 twelve-letter words that start with I, plus 1,579 rare ones.

What are common twelve-letter words that start with I?

intelligence, independence, introduction, increasingly, intellectual, intervention, incorporated and installation.

Which of the twelve-letter words that start with I has the highest letter score?

inexplicably scores 28 points with the standard letter tile values.

Related word lists

• 12-Letter Words
• Words That Start with I
• 11-Letter Words Starting with I
• 13-Letter Words Starting with I
• Q Words Without U