Source : Webster's Revised Unabridged Dictionary (1913)

Raceabout \Race"a*bout`\, n. (Naut.)
   A small sloop-rigged racing yacht carrying about six hundred
   square feet of sail, distinguished from a knockabout by
   having a short bowsprit.

Source : WordNet®

raceabout
     n : a small sloop having the keep of a knockabout but with finer
         lines and carrying more sail