chickweed

From Middle English chykwed, chykewode, chike wed, chikewed, chekwede, a variant of chykynwede, chekyn-wede, cheken-wede (literally “chicken-weed”), equivalent to chick +‎ weed.

Etymonline claims the name was apparently applied to many plants fit for chicken feed, which were called in Old English cicene mete (“chicken food”).