1. Having the physical appearance of death
   "a deathly pallor";
   - deathlike
    
2. Causing or capable of causing death
   "The snake's deathly venom required immediate treatment";
   - deadly, mortal

1. To a degree resembling death
   "he was deathly pale"
    
2. To an extreme degree
   "the night was deathly cold"; "as a child, I was deathly afraid of snakes";
   - extremely, exceedingly, super, hella [US, informal], stone

Derived forms: deathliest, deathlier

See also: dead, fatal, killing

Encyclopedia: Deathly