11-Letter Words Starting with O

All 183 eleven-letter words that start with O

OA

• oathbreaker20n. Someone who breaks an oath; a perjurer.

OB

• obfuscation18n. The act or process of obfuscating, or obscuring the perception of...
• obfuscatory21adj. Tending to obfuscate; intended to conceal the truth by confusion.
• objectified26adj. Treated as an object.
• objectively28adv. In an impartial, objective manner.
• objectivism27n. The state of being objective; objectivity.
• objectivist25adj. Of or pertaining to objectivism.
• objectivity28n. The state of being objective, just, unbiased, and not influenced by...
• obliterated14adj. Destroyed; (loosely) broken beyond repair.
• obliterator13n. One who obliterates.
• obliviously19adv. In an oblivious manner.
• obnoxiously23adv. In an obnoxious manner.
• obscuration15n. The state of being obscured.
• observation16n. The act of observing, and the fact of being observed (see observance).
• observatory19n. A place where stars, planets and other celestial bodies are observed...
• obsessional13adj. Marked by obsession.
• obsessively19adv. In an obsessive manner.
• obsolescent15adj. In the process of becoming obsolete, but not obsolete yet.
• obstinately16adv. In an obstinate manner.
• obstruction15n. The act of obstructing, or state of being obstructed.
• obstructive18adj. Causing obstructions.
• obtrusively19adv. In an obtrusive manner.
• obviousness16n. The characteristic of being obvious.

OC

• occipitalis17n. A muscle of the head that arises from the lateral two-thirds of the...
• occultation15n. An astronomical event that occurs when one celestial object is hidden...

OD

• odontoblast14n. A cell on the outer surface of dental pulp that produces tooth dentin.
• odontogenic15adj. Of or pertaining to the formation and development of teeth.
• odoriferous15adj. Having an odor or fragrance.

OF

• offensively23adv. In an offensive manner.
• offhandedly25adv. In or with an offhand manner.
• officership24n. The position or role of an officer.
• officialdom22n. The people elected to government or employed in the civil service.
• officiously22adv. In an officious manner.

OK

• okonomiyaki24n. A Japanese style of savoury pan-fried thick pancake including a mixture...

OL

• oligochaete17n. Any of various hermaphroditic aquatic and terrestrial annelid worms, of...
• oligoclonal14adj. Relating to an oligoclone, or to just a few clones.

OM

• omnichannel18adj. Integrating all physical (offline) and digital contact channels to...
• omnipotence17n. Unlimited power; commonly attributed to a deity or deities.
• omnipresent15adj. Being everywhere simultaneously.
• omniscience17n. The capacity to know everything.
• omphalocele20n. A hernia of the navel.

ON

• oncogenesis14n. The formation and development of tumors.
• oncological16adj. Of or pertaining to oncology.
• oncoprotein15n. A protein that is coded for by an oncogene.
• ondansetron12n. A carbazole derivative (trademark Zofran), C₁₈H₁₉N₃O, that is a...
• onomasticon15n. A book, list, or vocabulary of names, especially of people.
• ontogenesis12n. The generation and development of an individual organism from...
• ontogenetic14adj. Of or relating to ontogenesis.
• ontological14adj. Of or relating to ontology.

OP

• opalescence17n. The state of being opalescent.
• operability18n. The extent to which a system or device is operable.
• operational13adj. Of or relating to operations, especially military operations.
• operatively19adv. In an operative manner.
• opinionated14adj. Having very strong opinions.
• opportunely18adv. In a manner suitable for some particular purpose.
• opportunism17n. The practice of taking advantage of any situations or people to achieve...
• opportunist15n. Someone who takes advantage of any opportunity to advance their own...
• opportunity18n. A chance for advancement, progress or profit.
• opprobrious17adj. Causing opprobrium; offensive and shameful.
• optionality16n. The value of additional optional investment opportunities available...
• optogenetic16adj. Generated by light.
• optometrist15n. A person trained and skilled in examining and testing the eyes for...

OR

• orbicularis15n. A muscle surrounding an opening.
• orchestrate16v. To arrange or score music for performance by an orchestra.
• orchestrion16n. A mechanical multiple musical instrument designed to sound like an...
• orchiectomy23n. The surgical removal of one or both testes.
• orderliness12n. The fact of having a regular, proper and systematic arrangement.
• ordinariate12n. The office of a Roman Catholic ordinary, especially a bishop.
• orecchiette18n. A type of pasta, made with the thumb from a small disk, typically from...
• organically17adv. In an organic manner.
• orientalism13n. The tendency to represent eastern subjects, to assume stylistical...
• orientalist11adj. Of the West, to take in aspects of the East; pertaining to the...
• orientating12adj. That changes an orientation.
• orientation11n. The determination of the relative position of something or someone.
• originalism14n. The view that a text should be interpreted according to the intent of...
• originalist12n. One who has, or tends to have, original ideas.
• originality15n. The quality of being original or novel.
• origination12n. The process of bringing something into existence.
• originative15adj. That originates; creative.
• ornithology18n. The branch of zoology that deals with the scientific study of birds.
• ornithopter16n. An aircraft that generates lift through the flapping of its wings.
• orthodontia15n. Synonym of orthodontics.
• orthodontic17adj. Of, or relating to the dental speciality of orthodontics.
• orthography23n. A method of representing a language or the sounds of language by...
• orthologous15adj. Exhibiting orthology; having been separated by a speciation event....
• orthonormal16adj. Of a set of vectors, both orthogonal and normalized.
• orthopedics19n. The branch of medicine that deals with the prevention or correction of...
• orthopedist17n. A surgeon who specializes in orthopedics.
• orthostatic16adj. Relating to orthostasis or orthostatism.
• orthotropic18adj. Growing vertically, either upwards or downwards.

OS

• oscillating14adj. Moving in a repeated back-and-forth motion; coming and going.
• oscillation13n. The act of oscillating or the state of being oscillated.
• oscillatory16adj. That oscillates; oscillating.
• oseltamivir16n. An antiviral drug that is taken orally in the form of its phosphate...
• osmotically18adv. In an osmotic manner.
• ostentation11n. Ambitious display; vain show; display intended to excite admiration or...
• osteocalcin15n. A protein, found in bone and dentin and manufactured by osteoblasts...
• osteopathic18adj. Of or pertaining to osteopathy or osteopathic medicine.
• osteopontin13n. A sialopontin found in bone tissue.
• ostracizing23n. An act of ostracization.

OT

• otherworldy21adj. Synonym of otherworldly.
• otoacoustic15adj. Of or pertaining to sounds generated by the inner ear.
• ototoxicity23n. Damage to the ear, specifically the cochlea and sometimes the...

OU

• outbreeding15n. The breeding of unrelated (or only distantly related) individuals.
• outbuilding15n. A building, such as a barn, shed, or garage, that is separate from, but...
• outcropping18n. An outcrop.
• outcrossing14n. An organism produced by outcrossing.
• outdistance14v. To run farther or faster than another, or to finish a race with a large...
• outdoorsman14n. A man who spends time in outdoor pursuits or sports.
• outercourse13n. Sexual activity without vaginal or anal penetration.
• outflanking19n. The act of one who outflanks.
• outmaneuver16v. American standard spelling of outmanoeuvre.
• outreaching17n. An act of reaching out.
• outsmarting14n. An instance of somebody being outsmarted.
• outsourcing14n. The transfer of a business function to an external service provider.
• outspokenly20adv. In an outspoken manner.
• outstanding13adj. Prominent or noticeable; sovereign.

OV

• overachieve22v. To achieve more or at a higher level of quality than was expected.
• overanalyze26v. To analyze too much or in too much detail.
• overanxious21adj. Excessively anxious or nervous.
• overarching20adj. Arching over; that forms an arch overhead.
• overbalance18v. To be more important than; to outweigh.
• overbearing17adj. Overly bossy, domineering, arrogant, forceful, intense, or annoying.
• overbidding19n. An overbid; an excessively high offer.
• overbooking21n. An instance of selling or guaranteeing more seats than are available.
• overbreadth20n. The excessive broadness of a statute that, in proscribing unprotected...
• overcharged21adj. Overly charged; having too much electricity or some other form of...
• overcorrect18v. To correct too sharply or too much.
• overcrowded21adj. Containing too many occupants for an area of its size.
• overcurrent16n. A larger-than-intended electric current.
• overdeliver18v. To deliver in excess of a norm, standard, or requirement.
• overdressed16adj. Wearing too many clothes for the weather or the occasion.
• overdubbing20n. An instance of audio material being overdubbed.
• overexcited24adj. Excessively excited.
• overexposed24adj. Exposed too much, especially of film or a photograph.
• overexpress23v. To artificially express (a gene) in increased quantity.
• overfeeding19n. Excessive feeding.
• overfishing21n. Fishing that reduces the stock of remaining fish in an area to below...
• overfitting18n. The production of a statistical model that, due to an excess of...
• overflowing21n. Overflow.
• overgrazing25n. Excessive grazing to an extent that the land is damaged.
• overhanging19n. Synonym of overhang.
• overhauling18n. The act by which something is overhauled.
• overhearing18n. The act by which something is overheard.
• overheating18n. A situation where something is overheated.
• overhunting18n. Hunting at unsustainable levels.
• overindulge16v. To indulge to excess.
• overlanding16n. The practice of travelling overland, or moving stock overland.
• overlapping19adj. That overlaps something else.
• overloading16n. A type of polymorphism, where different functions, operators or...
• overmatched22adj. Outclassed; unable to compete.
• overnighter18n. A person who overnights, or stays overnight.
• overpayment21n. Payment exceeding the amount actually due.
• overpowered20adj. Subdued by superior force.
• overpricing19n. The setting of a price too high.
• overproduce19v. To produce more of something than one can use or sell.
• overpromise18v. To promise more than is delivered.
• overprotect18v. To protect to an excessive degree; to coddle.
• overstocked21adj. That has been stocked to an excessive degree; overfilled.
• overstretch19v. To stretch too far.
• overstuffed21adj. Filled beyond capacity.
• overthinker21n. One who overthinks.
• overthought21n. Excessive thought or thinking.
• overtopping19n. An instance of water going over the top of a barrier such as a sea wall...
• overtrading16n. The buying of a greater amount of goods than one can sell or pay for.
• overturning15n. The act by which something is overturned.
• overvaluing18n. An overvaluation.
• overvoltage18n. The difference between the electric potential of an electrode or cell...
• overwatered18adj. Watered too much.
• overweening18adj. Unduly confident; (sometimes also) arrogant.
• overwhelmed23adj. Emotionally overpowered.
• overwriting18n. Something written over something else.
• overwrought21adj. Excessively nervous, excited, tense, angry, anxious, or upset...
• overzealous23adj. Too zealous; too enthusiastic or fervent.
• oviposition16n. The process or instance of ovipositing, laying eggs.

OX

• oxaliplatin20n. A particular drug used in chemotherapy.
• oxandrolone19n. An androgenic anabolic steroid C₁₉H₃₀O₃ administered orally especially...
• oxidatively25adv. By means of oxidation.
• oxidization28n. Synonym of oxidation.
• oxychloride27n. A ternary compound of oxygen and chlorine.
• oxygenation22n. The process of reacting or treating something with oxygen.
• oxymorphone28n. A particular narcotic painkiller.
• oxyrhynchus32n. A fish with a pointed snout.

Questions about these words

How many eleven-letter words that start with O are there?

Word.ws lists 183 eleven-letter words that start with O, plus 1,225 rare ones.

What are common eleven-letter words that start with O?

opportunity, outstanding, operational, observation, orientation, overwhelmed, observatory and overlapping.

Which of the eleven-letter words that start with O has the highest letter score?

oxyrhynchus scores 32 points with the standard letter tile values.

Related word lists

• 11-Letter Words
• Words That Start with O
• 10-Letter Words Starting with O
• 12-Letter Words Starting with O
• Q Words Without U