Capable of causing death; mortal; fatal; destructive; certain or likely to cause death; as, a deadly blow or wound.
- Causing or tending to cause death: deadly weapons; a deadly spill of radioactive waste products. See Synonyms at fatal.
- Suggestive of death: a deadly pallor.
- Aiming or wanting to kill; implacable: deadly enemies.
- Destructive in effect: gave the film a deadly review.
- Tending to take away vitality, effectiveness, or force: the deadly habit of procrastination.
- Absolute; utter: deadly concentration.
- Extreme or terrible: worked under deadly strain.
- Extremely accurate; unerring: She is a deadly shot with the bow.
- Dull, tedious, and boring: a deadly prose style.
- So as to suggest death.
- To an extreme: deadly serious.