Poisonous plant and Plant life

Poisonous plant noun - A plant that when touched or ingested in sufficient quantity can be harmful or fatal to an organism.

Plant life and poisonous plant are semantically related. In some cases you can use "Plant life" instead a noun phrase "Poisonous plant".

Plant life noun - (botany) a living organism lacking the power of locomotion.

Poisonous plant and plant life are semantically related. Sometimes you can replace phrase "Poisonous plant" with "Plant life", this phrases are similar.