WordWeb Online

1. Brusque and surly and forbidding
   "gruff manner"; "a gruff reply";
   - crusty, curmudgeonly, ill-humored [US], ill-humoured [Brit, Cdn]
    
2. Deep and harsh sounding as if from shouting, illness or emotion
   "gruff voices"; "the dog's gruff barking";
   - hoarse, husky

Derived forms: gruffer, gruffest

See also: cacophonic, cacophonous, ill-natured

Encyclopedia: Gruff