ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun
Etymology: loco (II) + weed
1. : any of several leguminous plants (genera Astragalus and Oxytropis ) of western No. America that cause locoism in livestock
2. : any of several noxious or poisonous plants other than those causing locoism: as
a. West
(1) : a plant (as white snakeroot or rayless goldenrod) associated with alkali disease
(2) : water hemlock 1
(3) : any of several wild larkspurs of western No. America that are poisonous to livestock
b. slang : hemp 1 ; also : marijuana