English Words: U
23,789 words · Page 445 of 476
Any of various freshwater catfish that swim upside-down, such as Synodontis decorus, Synodontis multipunctatus, and especially Synodontis nigriventris
The twentieth letter of Classical and Modern Greek; the twenty-second letter of Old and Ancient Greek.
To teach (someone) additional skills, especially as an alternative to redundancy (firing).
Spelling & Dictionary Insight
The English alphabetical index for the letter U contains 23,789 headwords drawn from our Wiktionary-derived dictionary table. At 50 entries per page the browse splits into 476 pages, and you are currently viewing page 445. 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 "U" 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.