What is the meaning of Deadly?

Subject to death; mortal.

Causing death; lethal.

Aiming or willing to destroy; implacable; desperately hostile.

Very accurate (of aiming with a bow, firearm, etc.).

Very boring.

Excellent, awesome, cool.

Fatally, mortally.

In a way which suggests death.

Extremely, incredibly.

Source: wiktionary.org