Words That Start with IO

There are 26 words that start with IO on Word.ws, from 2 to 13 letters. The most common length is 6 letters (7 words). The words used most often are ion, io, ionic, iodine and ionization.

Meanings from Wiktionary. Not an official Scrabble, Words With Friends or Wordle word list.

2-letter words that start with IO

io2n. A type of moth, the io moth.

3-letter words that start with IO

ion3n. An atom or group of atoms bearing an electrical charge, such as the...

4-letter words that start with IO

iode5n. Synonym of iodine.
iora4n. Any of a group of passerine birds, of the genus Aegithina, found in...
iota4n. The ninth letter of the Greek alphabet (Ι, ι).

5-letter words that start with IO

ionic7adj. Of, relating to, or containing ions.

6-letter words that start with IO

iodate7n. The anion IO₃⁻; any salt of iodic acid.
iodide8n. A binary compound of iodine and another element or radical.
iodine7n. A chemical element (symbol: I) with an atomic number of 53; one of the...
iolite6n. The clear variety of cordierite, sometimes used as a gem.
ionics8n. The study of ionic conductors.
ionise6v. Ionize.
ionize15v. To dissociate atoms or molecules into electrically charged species; to...

7-letter words that start with IO

iodized18adj. Treated with iodine or an iodide.
ionizer16n. A device that ionizes.
ionomer9n. A polymer, or a biological macromolecule (such as a protein) in which a...

8-letter words that start with IO

iodoform14n. A halogenated hydrocarbon, CHI₃; a yellow crystalline compound...
ionizing18adj. Capable of producing ions.

9-letter words that start with IO

iodinated11adj. Treated or reacted with iodine or hydroiodic acid.
ionizable20adj. Capable of being ionized.
ionophore14n. Any substance that can transfer ions from a hydrophilic medium (such as...

10-letter words that start with IO

ionization19n. Any process that leads to the dissociation of a neutral atom or...
ionosphere15n. The part of the Earth's atmosphere beginning at an altitude of about 50...
ionotropic14adj. Of, pertaining to, or exhibiting ionotropy.

11-letter words that start with IO

ionospheric18adj. Of or pertaining to the ionosphere.

13-letter words that start with IO

iontophoresis18n. A treatment in which electrodes are put in contact with tissue and a...

223 rare words that start with IO

Questions about these words

How many words that start with IO are there?: Word.ws lists 26 words that start with IO, plus 223 rare ones.
What are common words that start with IO?: ion, io, ionic, iodine, ionization, iota, ionizing and iodide.
Which of the words that start with IO has the highest letter score?: ionizable scores 20 points with the standard letter tile values.

Related word lists

Word lists and meanings adapted from the Wiktionary entry of each word. Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws left out names, abbreviations, misspellings and offensive words, and ordered the most common words by how often they appear in English (wordfreq). Meanings from Wiktionary; this is not an official Scrabble, Words With Friends or Wordle word list. Wiktionary data of 2026-09-02.

Cite this page: “Words That Start with IO: 26 Words by Length.” Word.ws, https://word.ws/words/starting-with-io. Based on Wiktionary, CC BY-SA 4.0.