on ‧ ion S3 /ˈʌnjən/ BrE AmE noun [uncountable and countable]
[ Date: 1100-1200 ; Language: Old French ; Origin: oignon , from Latin unio ]
a round white vegetable with a brown, red, or white skin and many layers. Onions have a strong taste and smell:
Chop the onions finely.
red onions
home-made onion soup