onion weed
/ˈʌnjən ˌwiːd/noun
1 Australian. Any of various onion-like plants of the family Liliaceae occurring in Australia, chiefly as naturalized weeds; especially Asphodelus fistulosus, with white or pink five-petalled flowers and edible bulbs, native to southern Europe.
2 NZ. Any of several plants of the onion genus Allium occurring in New Zealand as naturalized weeds.
Origin
Early 20th century; earliest use found in Alfred Ewart (1872–1937), botanist. From onion + weed.