U definition and meaning | Collins English Dictionary (2025)

Table of Contents

U u in British English U in British English 1 U in British English 2 U. in British English U in American English 1 U in American English 2 U in American English 3 U in American English 4 u in American English 1 u in American English 2 U in American English U in American English 1 U in American English 2 U in American English 3 U in American English 4 u. in American English U. in American English Word lists with

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U

also u (juː ) (plural U's, u's )

1.variable noun A1

U is the twenty-first letter of the English alphabet.

U or u is used as an abbreviation for words beginning with 'u', such as 'unit', 'united', or 'University'.

u in British English

or U (juː )

nounWord forms: plural u's, U's or Us

the 21st letter and fifth vowel of the modern English alphabet

any of several speech sounds represented by this letter, in English as in mute, cut, hurt, sure, pull, or minus

something shaped like a U

(in combination)

a U-bolt

a U-turn

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U in British English 1

symbol for

united

unionist

university

4.(in Britain)

universal (used to describe a category of film certified as suitable for viewing by anyone)

(as modifier)

a U film

5. chemistry

uranium

6. biochemistry

uracil

abbreviation for

7. messaging & social media

you

adjective

8. British old-fashioned, informal

(esp of language habits) characteristic of or appropriate to the upper class

Compare non-U

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U in British English 2

(uː )

noun

(in Myanmar) a title of respect for men, equivalent to Mr

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U. in British English

abbreviation for

1. mathematics

union

unit

united

university

upper

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U in American English 1

(ju )

adjective Informal

of the upper or wealthy class, esp. the British upper class, as characterized by supposedly definitive usages, accent, behavior, tastes, etc.

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U in American English 2

uncle

Union

United

University

uracil

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U in American English 3

kosher (sense 1)

often enclosed in a circle (Ⓤ)

Word origin

U(nion of Orthodox Hebrew Congregations)

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U in American English 4

Chemistry

uranium

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u in American English 1

(ju ) or U (ju )

nounWord forms: plural U's or u's

the twenty-first letter of the English alphabet: formerly a variant of V, v; not until the 18th cent. was it established as a vowel symbol only

any of the speech sounds that this letter represents, as, in English, the vowel ( (ʌ) ) of cut, ( (ʊ) ) of bush, or ( (u) ) of rude, or the semivowel (w) of win

a type or impression for u or U

the twenty-first in a sequence or group

an object shaped like U

adjective

of u or U

twenty-first in a sequence or group

shaped like U

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u in American English 2

atomic mass unit

unit(s)

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U in American English

(juː) or u (juː)

nounWord forms: plural U's or Us, u's or us

the 21st letter of the English alphabet, a vowel

any spoken sound represented by the letter U or u, as in music, rule, curious, put, or jug

something having the shape of a U

a written or printed representation of the letter U or u

a device, as a printer's type, for reproducing the letter U or u

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U in American English 1

(juː)

pronoun

(pronunciation spelling)

you

Shoes Fixed While U Wait

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U in American English 2

(juː)

adjective

informal

characteristic of or appropriate to the upper class, esp. of Great Britain

Word origin

[u(pper class)]

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U in American English 3

(uː)

noun

a Burmese title of respect applicable to a man: used before the proper name

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U in American English 4

symbol

1.(on a packaged product)

certified as kosher by the Union of Orthodox Hebrew Congregations

the 21st in order or in a series, or, when I is omitted, the 20th

3.Chemistry

uranium

4.Biochemistry

uracil

5.Thermodynamics See internal energy

6.(formerly in Britain)

a designation for motion pictures determined as being acceptable for viewing by all age groups

Compare A2 (sense 11), AA2 (sense 5), X2 (sense 9)

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u. in American English

abbreviation

and

uniform

unit

unsatisfactory

upper

Word origin

[(def. 1) ‹ G und]

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U. in American English

abbreviation

uncle

and

uniform

union

unit

united

university

unsatisfactory

upper

Word origin

[(def. 2) ‹ G und]

Word lists with

text messaging abbreviations and symbols