English Words: O
15,494 words · Page 86 of 310
A systemic organophosphorous insecticide and acaricide used in horticulture and agriculture.
An exclamation of extreme surprise or excitement (usually facetious, sarcastic, or exaggerated).
A Japanese custom in which unattached individuals are introduced to each other to consider the possibility of marriage.
The 15th letter of the Classical and Modern Greek alphabets (16th in Ancient and Old Greek), used in ordering lists as in naming (astronomy) the 15th star of a constellation or (epidemiology) the 15th discovered major variant of a disease.
The highly virulent B.1.1.529 strain of the SARS-CoV-2 virus that causes COVID-19.
A random fortune, often written on a strip of paper or on a stick of bamboo, available at Japanese shrines in exchange for a small offering.
An orthorhombic-dipyramidal blue mineral containing aluminum, boron, iron, magnesium, oxygen, and silicon.
A souvenir, often candy or any another edible item, purchased for coworkers in Japanese culture.
One of the conical substructures which make up the eyes of invertebrates with compound eyes.
An intraventricular catheter system consisting of a catheter in one lateral ventricle attached to a reservoir implanted under the scalp, used for the aspiration of cerebrospinal fluid or for the delivery of drugs.
Spelling & Dictionary Insight
The English alphabetical index for the letter O contains 15,494 headwords drawn from our Wiktionary-derived dictionary table. At 50 entries per page the browse splits into 310 pages, and you are currently viewing page 86. Every row above is a dictionary-backed entry with a canonical slug, and each links through to a full definition page with pronunciation, senses, etymology, and related-word data where available.
On this page 50 of 50 entries carry a part-of-speech tag and 50 carry at least one stored definition. Coverage varies across letters because Wiktionary volunteers build entries at different speeds for different parts of the alphabet, letters with common starting sounds (S, C, T, P) usually have the densest coverage, while less frequent starters (X, Q, Z) tend to have shorter but more specialised lists. PlainSpell surfaces whatever data is present and links back to the source when a definition is not yet recorded.
For readers using this index as a spelling reference, the guarantee is that every form you see on the list is a documented English headword, not a guess, not a derived inflection lacking a lemma row. If a word you expected to find is absent from the "O" list, it usually means the form exists only as an inflection of another lemma (e.g. a past participle stored under the infinitive) or the entry has not yet been imported from Wiktionary. Use the search bar or the misspelling lookup to resolve these cases.