Source : Webster's Revised Unabridged Dictionary (1913)

Brunt \Brunt\ (br[u^]nt), n. [OE. brunt, bront, fr. Icel. bruna
   to rush; cf. Icel. brenna to burn. Cf. {Burn}, v. t.]
   1. The heat, or utmost violence, of an onset; the strength or
      greatest fury of any contention; as, the brunt of a
      battle.

   2. The force of a blow; shock; collision. ``And heavy brunt
      of cannon ball.'' --Hudibras.

            It is instantly and irrecoverably scattered by our
            first brunt with some real affair of common life.
                                                  --I. Taylor.

Source : WordNet®

brunt
     n : main force of a blow etc; "bore the brunt of the attack"