u has definitions from the fields of chemistry,physics,biology,biochemistry
1
[ pronoun ] pronoun, second person singular

Synonyms

you thee ye thou

2
[ adjective ] (chiefly British) of or appropriate to the upper classes especially in language use

Related terms

UK upper-class

3
[ noun ] (biology,chemistry,biochemistry) a nitrogen-containing base found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine

Synonyms

uracil

4
[ noun ] the 21st letter of the Roman alphabet

Related terms

letter Roman_alphabet

5
[ noun ] (chemistry,physics) a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons
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