adj. dead·li·er, dead·li·est 1. Causing or tending to cause death: deadly weapons; a deadly spill of radioactive waste products. See Synonyms at fatal. 2. Suggestive of death: a deadly pallor. 3. Aiming or wanting to kill; implacable: deadly enemies. 4. a. Destructive in effect: gave the film a deadly review. b. Tending to take away vitality, effectiveness, or force: the deadly habit of procrastination. 5. Absolute; utter: deadly concentration. 6. Extreme or terrible: worked under deadly strain. 7. Extremely accurate; unerring: She is a deadly shot with the bow. 8. Dull, tedious, and boring: a deadly prose style. adv. 1. So as to suggest death. 2. To an extreme: deadly serious. deadli·ness n. |
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