poisonous
UK[ˈpɔɪzənəs]US[ˈpɔɪzənəs]
adj
containing poison; capable of causing illness or death if taken into the body
adj
extremely unpleasant or malicious
Morpheme Breakdown
poison
ous
poison
substance causing harm
ous
adjective suffix
Etymology
the word 'poisonous' has a history rooted in the act of drinking. its core, 'poison', descends from the latin potio, meaning 'a drink' or 'potion'. this term evolved in medieval latin and old french to specifically denote a medicinal or magical draught, which could be either curative or deadly. the suffix '-ous', from latin -osus meaning 'full of', was attached to form the adjective, shifting the meaning from the substance itself to the characteristic of being full of or containing that harmful substance. thus, the literal 'full of a (deadly) drink' transformed into the modern abstract sense of being capable of causing harm or death.
Analysis
Structure: poison (substance causing harm) + ous (adjective suffix)
poison (from latin potio, potionis meaning 'a drink, potion, poisonous draught', via old french puison, poison; functions as the core root noun). ous (from latin -osus, meaning 'full of, characterized by'; functions as an adjective-forming suffix).
Examples
some mushrooms are highly poisonous and should never be eaten.
he gave her a poisonous look before turning away.
the factory was accused of dumping poisonous waste into the river.