deadlier

Adjective

deadly (comparative deadlier or more deadly, superlative deadliest or most deadly)

1. (obsolete, rare) Subject to death; mortal.
   • […]he ſuffred hym ſelfe to be made mortall and dedly, that innocent & gyltles in hym ſelfe: he myght be ſlayne & deye for the gylty man.1541, Rychard [W]hitforde, [D]yuers holy inſtrucyons and teachynges very neceſſarye for the helth of mannes ſoule […] , London: [W]yllyam Myddylton, page 36
2. Causing death; lethal.
   • But then I had the [massive] flintlock by me for protection. ¶[…]The linen-press and a chest on the top of it formed, however, a very good gun-carriage; and, thus mounted, aim could be taken out of the window[…], and a 'bead' could be drawn upon Molly, the dairymaid, kissing the fogger behind the...1879, R[ichard] J[efferies], chapter 1, in The Amateur Poacher, London: Smith, Elder, & Co., […], →OCLC
3. Aiming or willing to destroy; implacable; desperately hostile.
   • deadly enemies
4. Very accurate (of aiming with a bow, firearm, etc.).
   • Its deadly aim at vast distances, which condition of the mechanical power brought has made it the dread of the sepoys, who term it "the gun that kills without making any sound," contrasts strangely with the performances of Brown Bess of old, which at any range beyond a hundred yards was so...1858, “Woolwich Arsenal”, in The Living Age, volume 57, page 201
5. (informal) Very boring.
   • “I don't mean all of your friends—only a small proportion—which, however, connects your circle with that deadly, idle, brainless bunch—the insolent chatterers at the opera, the gorged dowagers, the worn-out, passionless men, the enervated matrons of the summer capital,[…]!”1907 August, Robert W[illiam] Chambers, chapter VI, in The Younger Set, New York, N.Y.: D. Appleton & Company, →OCLC
6. (Ireland, Newfoundland, informal, Australian Aboriginal) Excellent, awesome, cool.

See all 9 meanings of deadly