English Words: O
15,494 words · Page 197 of 310
The basic thermodynamic cycle of the normal four-stroke internal combustion engine: isentropic compression, constant-volume heat addition, isentropic expansion, and constant-volume heat rejection.
An upholstered sofa, without arms or a back, sometimes with a compartment for storing linen etc.
A large former Turkish empire which began as a sultanate centered in modern Turkey and at its height ruled over much of Southeast Europe, West Asia and North Africa; founded in the late 13th century, it lasted until the 1920s.
A nation-building ideology, put forward in the late days of the Ottoman Empire, that afforded equal status to Muslims and non-Muslims.
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 197. 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.