u

1 of 5

noun

ˈyü How to pronounce u (audio)
plural u's or us ˈyüz How to pronounce u (audio)
often capitalized, often attributive
1
a
: the 21st letter of the English alphabet
b
: a graphic representation of this letter
c
: a speech counterpart of orthographic u
2
: a graphic device for reproducing the letter u
3
: one designated u especially as the 21st in order or class
4
[abbreviation for unsatisfactory]
a
: a grade rating a student's work as unsatisfactory
b
: one graded or rated with a U
5
: something shaped like the letter U

u

2 of 5

abbreviation (1)

1
unit
2
unsymmetrical
3
physics up (see up entry 4 sense 5)
4
upper

U

3 of 5

adjective

ˈyü How to pronounce U (audio)
: characteristic of the upper classes

U

4 of 5

abbreviation (2)

1
unsatisfactory
2
uracil

U

5 of 5

symbol

uranium

Example Sentences

Noun There are three u's in “unusual.” a word that starts with u

Word History

Etymology

Adjective

upper class

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1a

Adjective

1954, in the meaning defined above

Time Traveler
The first known use of u was before the 12th century

Phrases Containing u

Dictionary Entries Near u

Tzutuhil

u

U

See More Nearby Entries 

Cite this Entry

“U.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/u. Accessed 7 Dec. 2022.

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Kids Definition

u

noun
ˈyü
often capitalized
: the 21st letter of the English alphabet

Medical Definition

U

1 of 2 abbreviation
uracil

U

2 of 2 symbol
uranium

More from Merriam-Webster on u

Nglish: Translation of u for Spanish Speakers

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