The Collaborative International Dictionary of English v.0.48:

Hoarse \Hoarse\, a. [Compar. Hoarser, superl. Hoarsest.]
   [OE. hors, also hos, has, AS. h[=a]s; akin to D. heesch, G.
   heiser, Icel. h[=a]ss, Dan. h[ae]s, Sw. hes. Cf. Prov. E.
   heazy.]
   1. Having a harsh, rough, grating voice or sound, as when
      affected with a cold; making a rough, harsh cry or sound;
      as, the hoarse raven.
      [1913 Webster]

            The hoarse resounding shore.          --Dryden.
      [1913 Webster]

   2. Harsh; grating; discordant; -- said of any sound.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hoarse
    adj 1: deep and harsh sounding as if from shouting or illness or
           emotion; "gruff voices"; "the dog's gruff barking";
           "hoarse cries"; "makes all the instruments sound powerful
           but husky"- Virgil Thomson [syn: gruff, hoarse,
           husky]

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "hoarse":
   blurred, brassy, brazen, breathy, choked, choking, coarse, cracked,
   croaking, croaky, drawling, drawly, dry, dysphonic, grating, gruff,
   guttural, harsh, harsh-sounding, hawking, husky, inarticulate,
   indistinct, jarring, lisping, metallic, mispronounced, muzzy,
   nasal, quavering, ragged, rasping, raucid, raucous, rough, roupy,
   rude, shaking, shaky, snuffling, squawking, squawky, stertorous,
   stifled, strangled, strident, stridulous, thick, throaty, tinny,
   tremulous, twangy, velar