Definition of onion
1 : a widely cultivated Asian herb (Allium cepa) of the lily family with pungent edible bulbs; also : its bulb
2 : any of various plants of the same genus as the onion
onionyplay \-yə-nē\ adjective
Examples of onion in a sentence
The recipe calls for chopped onions.
He is growing onions in the garden this year.
The recipe calls for chopped onion.
Origin and Etymology of onion
Middle English, from Anglo-French oignon, from Latin union-, unio
First Known Use: 14th century
ONION Defined for English Language Learners
Definition of onion for English Language Learners
: a round vegetable that is usually white, yellow, or red and has a strong smell and taste
ONION Defined for Kids
Definition of onion for Students
: the roundish edible bulb of a plant related to the lily that has a sharp odor and taste and is used as a vegetable and to season foods
Seen and Heard
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