poisonous plant poi·so·nousp·lant uncommon noun 1. a plant that when touched or ingested in sufficient quantity can be harmful or fatal to an organism Synonymspoisonous plant Related words Broader terms plant Narrower terms aconitebaneberryhelleboredogbaneoleandergloriosasnowberryAmerican holly WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
