From Biology-Online Dictionary | Biology-Online Dictionary


1. Capable of causing death; mortal; fatal; destructive; certain or likely to cause death; as, a deadly blow or wound.

2. Aiming or willing to destroy; implacable; desperately hostile; flagitious; as, deadly enemies. Thy assailant is quick, skillful, and deadly. (Shak)

3. Subject to death; mortal.

(Science: botany) deadly nightshade, a poisonous plant; belladonna. Of an instrument of certain death; deadly poisons; lethal weapon; a lethal injection.