There are currently 3 astronomical definitions for the tag 'comet'.
comet
kreutzsungrazer, aperiodiccomet, longperiodcomet, periodiccomet
oortcloud, solarsystem, coma, dirtysnowballtheory, dust, envelope, halo, interplanetarymatter, jet, meteorstream, meteorite, meteoroiddustcloud, meteoroid, nucleuscelestialobject, parabolicorbit, streamer, tail