Word: u

a

• (chiefly British) of or appropriate to the upper classes especially in language use

n

• a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons
• a nitrogen-containing base found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine
• the 21st letter of the Roman alphabet

PROTOTYPE PAGE, Source: WordNet