DEADLY
deadly
(adjective) (of a disease) having a rapid course and violent effect
deadly, deathly, mortal
(adjective) causing or capable of causing death; “a fatal accident”; “a deadly enemy”; “mortal combat”; “a mortal illness”
deadly, lethal
(adjective) of an instrument of certain death; “deadly poisons”; “lethal weapon”; “a lethal injection”
baneful, deadly, pernicious, pestilent
(adjective) exceedingly harmful
deadly, mortal
(adjective) involving loss of divine grace or spiritual death; “the seven deadly sins”
deadly, venomous, virulent
(adjective) extremely poisonous or injurious; producing venom; “venomous snakes”; “a virulent insect bite”
madly, insanely, deadly, deucedly, devilishly
(adverb) (used as intensives) extremely; “she was madly in love”; “deadly dull”; “deadly earnest”; “deucedly clever”; “insanely jealous”
deadly, lifelessly
(adverb) as if dead
Source: WordNet® 3.1
Etymology
Adjective
deadly (comparative deadlier or more deadly, superlative deadliest or most deadly)
(obsolete) Subject to death; mortal.
Causing death; lethal.
Aiming or willing to destroy; implacable; desperately hostile.
Very accurate (of aiming with a bow, firearm, etc.).
(informal) Very boring.
(informal) Excellent, awesome, cool.
Adverb
deadly (comparative more deadly, superlative most deadly)
(obsolete) Fatally, mortally.
In a way which suggests death.
Extremely.
Usage notes
Some adjectives commonly collocating with deadly: serious, clever, good
Source: Wiktionary
Dead"ly, a.
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. [Obs.]
The image of a deadly man. Wyclif (Rom. i. 23).
Deadly nightshade (Bot.), a poisonous plant; belladonna. See under
Nightshade.
Dead"ly, adv.
1. In a manner resembling, or as if produced by, death. "Deadly
pale." Shak.
2. In a manner to occasion death; mortally.
The groanings of a deadly wounded man. Ezek. xxx. 24.
3. In an implacable manner; destructively.
4. Extremely. [Obs.] "Deadly weary." Orrery. "So deadly cunning a
man." Arbuthnot.
Source: Webster’s Unabridged Dictionary 1913 Edition