English Words: O

15,494 words · Page 302 of 310

oxidopaminenoun

A neurotoxin used by scientists for selective killing of dopaminergic and noradrenergic neurons.

oxidoreductasenoun

Any enzyme that catalyzes an oxidation-reduction (redox) reaction.

oxidoreductionnoun

Synonym of redox reaction.

oxidoresistancenoun

resistance to redox reactions

oxidoresistantadj

resistant to redox reactions

oxidosensitivitynoun

sensitivity to redox reactions

An amphetamine stimulant drug.

A particular narcotic.

Reaction with, or conversion into an oxime

Any of a class of organic compounds, of general formula RR'C=NOH, derived from the condensation of an aldehyde (R' = H) or ketone with hydroxylamine.

A device that measures the quantity of oxygen in something, particularly air in the atmosphere.

Relating to oximetry

The measurement of the oxygen level in arterial blood

The complex formed between oxine and a metal ion.

Pertaining to, or designating, certain compounds of iodine and oxygen.

A nootropic drug of the racetam family.

Resembling or characteristic of an ox.

In a manner like that of an ox.

All oxen, considered as a group.

An old land measure, equivalent to eight acres.

Having no ox or oxen.

A suburb of Wolverhampton, West Midlands, England (OS grid ref SJ9101).

Resembling or characteristic of an ox: strong, foolish, etc.

A small, young, or miniature ox.

A plant of species Primula elatior, similar to cowslip (Primula veris) but with larger, pale yellow flowers.

The largest city in Ventura County, California, United States.

A surname from German.

The London Underground rail network.

oxo-prefix

Oxygen.

glyoxylate

Alternative form of oxyacid.

oxoaldehydenoun

Any aldehyde that also has an oxo/ketone group.

Any alkyl group in which a methylene group has been replaced by a carbonyl group.

Any amide of a ketocarboxylic acid

oxoammoniumnoun

Any of a class of cations of general formula RR^'N⁺=O

Any anion derived from an oxoacid

Relating to oxoanions.

oxoaporphinenoun

Any oxo derivative of an aporphine

oxobiodegradableadj

Alternative form of oxybiodegradable.

Any mixed oxide and borate

Any oxohalide in which the halide is bromide

oxobutanoatenoun

Any derivative of a butanoate in which a methylene group has been replaced by a carbonyl group

oxocarbazatenoun

A derivative of a carbazate in which a methylene group has been replaced by a carbonyl

Any organic compound containing only atoms of carbon and oxygen

oxocarboxylatenoun

Any derivative of a carboxylate in which a methylene group has been replaced by a carbonyl group

oxocarboxylicadj

Relating to a carboxylic acid in which a methylene group has been replaced by a carbonyl group

oxochloridenoun

Any oxohalide in which the halide is chloride

oxocholesterolnoun

Any derivative of cholesterol in which a methylene group has been replaced by a carbonyl group

Any complex (typically of a transition element) containing an oxo group

A linear terpenoid derived from the seaweed Cystoseira crinita, 12-hydroxy-6,10-dimethyldodeca-6,10-dien-2-one

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 302. 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.