U (letter)

U, u is a letter of the Latin alphabet. It is the twenty-first letter of most variants, being placed after T and before V, as is the case for instance in the English alphabet. The original alphabet in ancient Rome did not distinguish between U and V: the former was the lowercase form of the latter, and they represented both the vowel [u] and the semivowel [w].

The English name of U is pronounced [ˈjuː], like the words you and ewe.

Use in English
u can represent three back vowel sounds, one of which (û) has a variant with an initial semivowel, 'yû'; or it can be a semi-consonant sounding like 'w', most often after q.

Examples (the accents show stress and pronunciation: see English spellings):

The short sound: dúck, fún, úp, cúddle, lúst, múst, lúck, búbble, troúble, soúthern (but not sòuth), nút, cúp, fúss, búg, bús, stún, búlb, pútt golf (cf. pùt place), nún God (= nòne negative). The sound is a stressed schwa in American English, IPA 'ʌ' in standard British English.

Compare lúck and loòk (both pronounced loòk in demotic speech in Northern England: 'lùck'): ú, because it is a single letter and a short sound, is often followed by -ck.

A ú is written after an ò, though there is still only the one short sound, in Doúglas, floúrish, noúrish, yoúng, troúble, doúble (cf. BrE roûble, AmE rûble).

There are two different long sounds: one with an invisible consonantal y before it (as always found in eŵ as in feŵ or ieŵ as in vieŵ); and a plain oô sound (as in toô, foôd, noôn). The sound is always 'yû' initially: ûse (verb, voiced s; noun, unvoiced s), ûsual, Ûrals, ûríne.

Pronounced 'yû':  cûrious, mûcous, vácuum, Canûte, pûre, cûre, ukulèlê, bûte, cûte, fûtile, mûte, pûtrid, queûe line (*kyoô = cûe hint) and regarded as the more correct pronunciation in stûpid, nûclear, nûde. Pronounced 'oô' in British English: Lûke, lûnar, flûe chimney = flû influenza, blûe, glûe, rûde, rûle, rûmour, Rûfus, Rûpert, accrûe, scrûple. Pronounced 'yoô' in BrE (but can be 'oô' in AmE): tûne, tûbe, dûty.

Pronunciation depending on region and idiolect: lûred, lûrid, lûcid, Lithuânia, sûit, Surinám.

The sound with the invisible y can also be spelt eû: neûrotic, Eûrope, pneumônia, eûphony, psêud, psêudo- (and without the y sound in rheûmatism), or ûi as in  nûisance, though in this case the 'oô' sound, often after a liquid consonant, is more common: slûice, brûise, recrûit, crûise, frûit, jûice.

There is never any 'y' sound when the spelling is oû (except in the local pronunciation of Hoûston, Texas): soûp, groûp, throûgh, roûble (BrE; = AmE rûble), Loûvre, goûlash - though ou has other sounds: yoúng, troúble, doúble, fŏur, cŏurse, ŏught, nŏught, jöurney.

After j it is impossible to make a difference: Jûne, Jûpiter, jûniper, jûry, jûke-bóx, jûte, cf. choôse. There are no words beginning shû- (cf. shút) or chû- (cf. chúm) - except for the French chûte shaft = shoõt gun, which does not have the normal 'ch' sound.

Occasionally with the combination sû there is a tendency to palatalise fully and pronounce the s as sh, as for example in sûre certain, which BrE speakers can make sound like the name Shåw, and which never sounds like sewêr waste; and in íssue (*íshue - though there is a recent trend back to *íssyue) and tíssue. But most words do not palatalise: assûme has the y sound, as can sûit, while sûture and sûper have a plain s sound.

(The tendency noted above for BrE speakers to make sûre sound like Shåw used to be more widespread, as with, for example, secûrity pronounced *sekyŏrity: it can be heard in old British films.)

ù sounds like oò in foòt and occurs in a few common words: pùsh, bùsh, fùll, pùt, pùdding, coùld, woùld, shoùld (silent l’s in the last three).

In Welsh names such as Plaîd Cymru (*Plîde Cúmry), u is pronounced as ì/ỳ/êe.

Sounding like w
u is almost always the letter that follows q, where it is pronounced 'w': quêen, quénch, quâke, quíll, quést. And like w in ẁant, it has an effect on the following a, making it sound like 'ŏ' or 'ó' (or à in AmE):

uå sounding like 'wŏ': quårter, quårtz, squåll, quartét, quårt.

ùa sounding like 'wó' (= 'wà' in AmE): sqùalor, qùantity, qùadrangle, qùarrel.

In some words, mostly from Spanish, u can be pronounced 'w' without a preceding 'q': Nicarágua (-gwə, or, more traditionally, gûə), marijuàna (*mariyəwànə, -yû-àna), iguàna (*igwànə, or -gû-), Pápua (*Pápwə or *Pápuwə), guàno, Guàm; suède and persuâde, which rhyme with wâde, and assuâge, which rhymes with wâge.

Silent and redundant
A redundant u sometimes occurs in the middle of ŏr as ŏur in: 'fŏur, cŏurse, sŏurce, gŏurd.

Another redundant u occurs in the middle of ör as öur in jöurney, jöurnal, adjöurn, cöurteous, cöurtesey politeness (cf. cürtsey bow), scöurge and unstressed in Lúxembourg.

u is also silent before i in guîde, guílty, buíld, guíld, bíscuit, cïrcuit, and before e in guéss, guést, and usually in the ending -ue: tòngue, vâgue, rôgue, burlésque, baròque, unìque, grotésque, but not in âgûe or Móntagûe.

āunt and guàrd also have redundant u, as does gâuge (*gâje), though this can be spelt gâge in American.

In endings
-us is an ending with the schwa sound, most often in names: Dêlius, Míngus, Tåurus, Sagittãrius, Vênus, Sírius, Cánopus, Aquãrius, Pándarus, Lûpus, Cêtus, Arctûrus, Jûlius, Crássus, Cássius, Vílnius, Epicûrus, Confûcius and also in nouns: ábacus, sánctus, nímbus, sýllabus, ómnibus, détritus, crôcus.

But it’s -ous with adjectives: glorious, fûrious, têdious, pulchritûdinous, màrvellous.

uu is very rare and can be pronounced as one syllable 'yû' - as usually in vácûum - or as two syllables 'yû(w)ù' - as in contínûùm.

Irregular u’s
Also, in some BrE, u is pronounced 'f' in lieuténant (*lefténant) - though in AmE and most other BrE, it is a regular û. In the British Navy it is pronounced *lé-ténant.

For the many pronunciations of ough, see O.