adj. 25B6; adjective RISKY, dangerous, unsafe, perilous, precarious, fraught with danger; unpredictable, uncertain, chancy, high-risk, insecure, touch-and-go; informal dicey, hairy; Brit. informal dodgy.
safe, certain.
HAZARDOUS
Meaning of HAZARDOUS in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012