Synonyms for dangerous

modified

1. Not safe

   perilous, unsafe, hazardous, risky, precarious, treacherous, unprotected, unshielded, unsheltered, critical, serious, vulnerable, exposed, involving risk, full of risk, threatening, alarming, portentous, causing danger, insecure, ticklish, delicate, speculative, unstable, touchy, bad, fraught with danger, thorny, jeopardous, breakneck, chancy, uncertain, touch-and-go, shaky, slippery, unsteady, rickety, rocky, hairy*, unhealthy*, hot*, dicey*; see also endangered, uncertain 2, unsafe.

   Antonyms safe, sure, secure.

2. Involving an active threat

   menacing, threatening, serious, critical, impending, ominous, ugly, nasty, imminent, malignant, formidable, terrible, impregnable, armed, fatal, mortal, deadly, explosive, out of the frying pan and into the fire*, on a collision course*; see also ominous.

   Antonyms helpful*, innocent, beneficial.