WordNet (r) 3.0 (2006):

black humor
    n 1: the juxtaposition of morbid and farcical elements (in
         writing or drama) to give a disturbing effect [syn: black
         humor, black humour]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "black humor":
   Atticism, agile wit, burlesque, caricature, comedy, dry wit,
   esprit, farce, humor, irony, lampoon, nimble wit, parody,
   pleasantry, pretty wit, quick wit, ready wit, salt, sarcasm,
   satire, savor of wit, slapstick, slapstick humor, squib,
   subtle wit, travesty, visual humor, wit