Meaning

noun weedy annual grass often occurs in grainfields and other cultivated land; seeds sometimes considered poisonous

originFrom Middle English darnel, dernel, from Old Northern French darnelle ( > dialectal French dernelle, darnette), of Germanic origin, possibly Proto-West Germanic *darjan (“to harm, injure”). Displaced native Old English boþen. Related to Walloon darne, derne (“stunned, dazed, drunk”), Middle Dutch verdarnt, verdaernt (“stunned, dumbfounded, angry”). The association with being dazed or drunkenness…

Etymology from Wiktionary, CC BY-SA 3.0