The Collaborative International Dictionary of English v.0.48:

Morsel \Mor"sel\, n. [OF. morsel, F. morceau, LL. morsellus, a
   dim. fr. L. morsus a biting, bite, fr. mordere to bite; prob.
   akin to E. smart. See Smart, and cf. Morceau, Mordant,
   Muse, v., Muzzle, n.]
   1. A little bite or bit of food. --Chaucer.
      [1913 Webster]

            Every morsel to a satisfied hunger is only a new
            labor to a tired digestion.           --South.
      [1913 Webster]

   2. A small quantity; a little piece; a fragment.
      [1913 Webster]

WordNet (r) 3.0 (2006):

morsel
    n 1: a small quantity of anything; "a morsel of paper was all he
         needed"
    2: a small amount of solid food; a mouthful; "all they had left
       was a bit of bread" [syn: morsel, bit, bite]

Moby Thesaurus II by Grady Ward, 1.0:

90 Moby Thesaurus words for "morsel":
   ambrosia, atom, bait, bit, bite, bolus, bonne bouche, butt, cate,
   champ, chaw, chew, chip, choice morsel, chomp, chunk, clip,
   clipping, collop, crumb, cud, cut, cutting, dainty, delicacy,
   dessert, dollop, drop, end, fraction, fragment, gnash, gob, gobbet,
   goody, grain, granule, hunk, kickshaw, lump, manna, modicum,
   moiety, morceau, mouthful, munch, nectar, nibble, nip, paring,
   particle, patch, piece, pinch, quid, rasher, remnant, sample,
   savory, scoop, scrap, shard, shaving, shiver, shred, slice, sliver,
   smidgen, smidgin, smithereen, snack, snap, snatch, snick, snip,
   snippet, soupcon, speck, splinter, spoonful, stitch, stump,
   swallow, tag, taste, tatter, tidbit, titbit, treat, whit