A monocotyledonous plant (Allium cepa), allied to garlic, used as vegetable and spice. / The bulb of such a plant. / (uncountable) The genus Allium as a whole. / (slang, of a drug) An ounce.

plural of onion

A surname from Welsh [in turn originating as a patronymic].

Flavoured or made with onion.

(informal, rare) Flavoured with, or converted into, onion; made oniony.

A species of onion (Allium fistulosum).

A species of onion (Allium fistulosum) from Asia, with slender bulbs. / Any of several similar types of onion.

(US) scallion

a quantum well incorporated in a quantum dot

A cooked meal consisting of liver fillets with onions, especially sliced, and other seasoning.