Synonyms of perilous

Adjective

1. parlous, perilous, precarious, touch-and-go, dangerous (vs. safe), unsafe

usage: fraught with danger; "dangerous waters"; "a parlous journey on stormy seas"; "a perilous voyage across the Atlantic in a small boat"; "the precarious life of an undersea diver"; "dangerous surgery followed by a touch-and-go recovery"

Definition and meaning of perilous (Dictionary)