- (informal) Very boring.
- (obsolete) Subject to death; mortal.
- (by extension) Very accurate (of aiming with a bow, firearm, etc.).
- Aiming or willing to destroy; implacable; desperately hostile.
- (informal) Excellent, awesome, cool.
- Causing death; lethal.
- In a way which suggests death.
"Her face suddenly became deadly white."
- (obsolete) Fatally, mortally.
"deadly weary — Orrery.so deadly cunning a man — Arbuthnot."