Source : Webster's Revised Unabridged Dictionary (1913)

Loco \Lo"co\, n. (Bot.)
   Any one of various leguminous plants or weeds besides
   {Astragalus}, whose herbage is poisonous to cattle, as
   {Spiesia Lambertii}, syn. {Oxytropis Lambertii}.

Source : WordNet®

Oxytropis lambertii
     n : tufted locoweed of southwestern United States having purple
         or pink to white flowers [syn: {purple locoweed}, {purple
         loco}]