The Collaborative International Dictionary of English v.0.48:

innards \innards\ n.
   The internal organs of an animal collectively especially
   those in the abdominal cavity.

   Syn: viscera.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

innards
    n 1: internal organs collectively (especially those in the
         abdominal cavity); "`viscera' is the plural form of
         `viscus'" [syn: viscera, entrails, innards]

Moby Thesaurus II by Grady Ward, 1.0:

74 Moby Thesaurus words for "innards":
   abdomen, action, anus, appendix, blind gut, bowels, brain, cecum,
   census, clockworks, colon, composition, constituents, content,
   contents, divisions, drive train, duodenum, elements, endocardium,
   entrails, foregut, gear, giblets, gizzard, guts, heart, hindgut,
   index, ingredients, inner mechanism, insides, internals, intestine,
   inventory, inwards, items, jejunum, kidney, kishkes,
   large intestine, list, liver, liver and lights, lung, machinery,
   mechanism, midgut, motion, movement, movements, part, parts,
   perineum, power train, pump, pylorus, rectum, servomechanism,
   small intestine, spleen, stomach, stuffing, ticker, tripes,
   vermiform appendix, viscera, vitals, watchworks, wheels,
   wheels within wheels, whole, workings, works