WordWeb Online

1. Involving or causing danger or risk; liable to hurt or harm
   "a dangerous criminal"; "unemployment reached dangerous proportions";
   - unsafe
    
2. Causing fear or anxiety by threatening great harm
   "a dangerous operation";
   - grave, grievous, serious, severe, life-threatening

See also: breakneck, chanceful, chancy, critical, desperate, dicey, dodgy [Brit], hazardous, insecure, insidious, mordacious, on the hook, parlous, perilous, precarious, risky, self-destructive, suicidal, touch-and-go, treacherous, unreliable, unsafe, vulnerable, wild

Antonym: safe

Encyclopedia: Dangerous Dangerous, Dirty and Difficult job