Source : Webster's Revised Unabridged Dictionary (1913)

Machaerodus \Ma*ch[ae]"ro*dus\, Machairodus \Ma*chai"ro*dus\, n.
   [NL., fr. Gr. ? dagger + ? tooth.] (Paleon.)
   A genus of extinct mammals allied to the cats, and having in
   the upper jaw canine teeth of remarkable size and strength;
   -- hence called saber-toothed tigers.