References

u

letter

Also known as: U

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Last updated

July 23, 2026

Quick Summary

The letter "u" is the 21st letter of the English alphabet. It can be represented graphically or as a speech sound. The letter "u" can also be used as an abbreviation for "unsatisfactory" (a grade) or in physics to mean "up".12

While uncommon, the letter "u" can be doubled in certain words, such as "vacuum," "residuum," and "continuum". The symbol "U" is also used to represent the element uranium. There are thousands of words that begin with the letter "u".345

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q
…used only with a following u, the combination representing the unvoiced labiovelar sound in such words as quaestor. The combination of these two letters holds to the present day, and in modern English q is not used unless followed by u, even if, in words such as oblique, the sound…
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…used only with a following u, the combination representing the unvoiced labiovelar sound in such words as quaestor. The combination of these two letters holds to the present day, and in modern English q is not used unless followed by u, even if, in words such as oblique, the sound…
Read More