1. [ adjective ] causing or capable of causing death
Synonyms: mortal deathly

"a fatal accident" "a deadly enemy" "mortal combat" "a mortal illness"

Related terms: fatal
2. [ adjective ] of an instrument of certain death
Synonyms: lethal

"deadly poisons" "lethal weapon" "a lethal injection"

Related terms: fatal
3. [ adverb ] as if produced by death

"deadly pale" "a deadly paralytic stroke"

4. [ adjective ] (theology) involving loss of divine grace or spiritual death
Synonyms: mortal

"the seven deadly sins"

Related terms: theology unpardonable
5. [ adjective ] exceedingly harmful
Synonyms: pernicious pestilent baneful
Related terms: noxious
6. [ adverb ] (used as intensives) extremely
Synonyms: insanely deucedly devilishly madly

"she was madly in love" "deadly dull" "deadly earnest" "deucedly clever" "insanely jealous"

Related terms: intensifier
7. [ adjective ] extremely poisonous or injurious; producing venom
Synonyms: virulent venomous

"venomous snakes" "a virulent insect bite"

Related terms: toxic
8. [ adverb ] as if dead
Synonyms: lifelessly
Related terms: dead lifeless dead lifeless
9. [ adjective ] (of a disease) having a rapid course and violent effect
Related terms: virulent
Similar spelling:   detail