Disastrous is a related term of poisonous.
As adjectives the difference between disastrous and poisonous
is that disastrous is of the nature of a disaster; calamitous while poisonous is containing sufficient poison to be dangerous.
disastrous
English
Adjective
(
en adjective)
of the nature of a disaster; calamitous.
foreboding disaster; ill-omened.
Synonyms
* (calamitous) cataclysmic, catastrophic
* (ill-omened) ill-boding, , sinister
Derived terms
* disastrously
poisonous
English
Adjective
(
en adjective)
Containing sufficient poison to be dangerous
(of an animal) Inedible due to containing poison; poisonous to eat
Synonyms
* toxic, venomous, attery
Derived terms
* poisonousness