A person dedicated to a life of religion or monasticism, especially a member of an order without religious vows or a lay member of a religious community.

oblationnoun

The offering of worship, thanks etc. to a deity.

obligateverb

To bind, compel, constrain, or oblige by a social, legal, or moral tie.

obligatedadj

Committed.

obligationnoun

The act of binding oneself by a social, legal, or moral tie to someone.

obligationsnoun

plural of obligation

obligatoryadj

Imposing obligation, legally, morally, or otherwise; binding; mandatory.

obligeverb

To constrain someone by force or by social, moral or legal means.

obligedadj

Under an obligation to do something.

obligingadj

Happy and ready to do favours for others.

obliginglyadv

In an obliging manner; so as to oblige another; as a favour to another.

obliqueadj

Not erect or perpendicular; not parallel to, or at right angles from, the base.

obliquelyadv

In an oblique manner; sideways.

obliterateverb

To destroy (someone or something) completely, leaving no trace; to annihilate, to wipe out.

obliteratedadj

Destroyed; (loosely) broken beyond repair.

obliterationnoun

The total destruction of something.

oblivionnoun

The state of forgetting completely, of being oblivious, unconscious, unaware, as when sleeping, drunk, or dead.

obliviousadj

Lacking awareness; unmindful; unaware, unconscious of.

oblongadj

Having a length and width that are different; not square or circular.

oblongatanoun

Clipping of medulla oblongata.

obnoxiousadj

Extremely offensive or unpleasant; very annoying, contemptible, or odious.

obnoxiouslyadv

In an obnoxious manner.

oboenoun

A soprano and melody wind instrument in the modern orchestra and wind ensemble. It is a smaller instrument and generally made of grenadilla wood. It is a member of the double reed family.

obovateadj

Shaped like an egg, with the broad extremity located away from the base.

OBRname

Initialism of Office for Budget Responsibility.

Obradorname

A surname from Spanish

obsnoun

Police observation.

obsceneadj

Offensive to standards of decency or morality.

obscenelyadv

In an obscene manner; vulgarly.

obscenitynoun

Something that is obscene.

obscureadj

Dark, faint or indistinct.

obscurelyadv

In an obscure manner.

obscuritynoun

Darkness; the absence of light.

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 3. 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.