[1] : WordNet (r) 2.0

sailplane
     n : aircraft supported only by the dynamic action of air against
         its surfaces syn: glider
     v : fly a plane without an engine syn: soar
see also:
glider soar 

[2] : Moby Thesaurus II by Grady Ward, 1.0

26 moby thesaurus words for "sailplane":
   aeroplane, airlift, airplane, balloon, be airborne, cruise, drift,
   ferry, flit, fly, glide, glider, gliding machine, hop, hover,
   hydroplane, jet, navigate, rocket glider, sail, seaplane, soar,
   take the air, take wing, volplane, wing

Sailplane >> S Words
Sailplane, definition of term: Sailplane
sailplane_pag1.html