The Collaborative International Dictionary of English v.0.48:

Mite \Mite\ (m[imac]t), n. [AS. m[imac]te mite (in sense 1);
   akin to LG. mite, D. mijt, G. miete, OHG. m[imac]za; cf.
   Goth. maitan to cut.]
   1. (Zool.) A minute arachnid, of the order Acarina, of
      which there are many species; as, the dust mite, cheese
      mite, sugar mite, harvest mite, three-toed spider mite,
      etc. See Acarina.
      [1913 Webster]

   2. [D. mijt; prob. the same word.] A small coin formerly
      circulated in England, rated at about a third of a
      farthing. The name is also applied to a small coin used in
      Palestine in the time of Christ.
      [1913 Webster]

            Two mites, which make a farthing.     --Mark xii.
                                                  49.
      [1913 Webster]

   3. A small weight; one twentieth of a grain.
      [1913 Webster]

   4. Anything very small; a minute object; a very little
      quantity or particle.
      [1913 Webster]

            For in effect they be not worth a myte. --Chaucer.
      [1913 Webster]

WordNet (r) 3.0 (2006):

mite
    n 1: a slight but appreciable amount; "this dish could use a
         touch of garlic" [syn: touch, hint, tinge, mite,
         pinch, jot, speck, soupcon]
    2: any of numerous very small to minute arachnids often
       infesting animals or plants or stored foods

Moby Thesaurus II by Grady Ward, 1.0:

162 Moby Thesaurus words for "mite":
   ace, arachnid, arthropod, atom, bairn, bawbee, beetle, bit, bug,
   cat flea, caterpillar, centipede, cherub, chigoe, child, chilopod,
   chit, cockroach, crab, crown, crumb, dab, daddy longlegs, darling,
   diplopod, dog flea, dole, dollar, dot, dram, dribble, driblet,
   drop, droplet, dwarf, farthing, fiver, flea, fleck, florin, fly,
   flyspeck, fourpence, fourpenny, fragment, gnat, gobbet, grain,
   granule, grayback, groat, guinea, hair, half crown, half dollar,
   half rations, halfpenny, handful, harvestman, hexapod, innocent,
   insect, iota, jigger, jot, kid, kitten, lamb, lambkin, larva,
   little, little bit, little bugger, little fellow, little guy,
   little innocent, little one, little tad, little tot, lota, louse,
   mag, maggot, meg, mere subsistence, microbe, microorganism, midge,
   millepede, millipede, minim, minimum, minutia, minutiae, modicum,
   molecule, monkey, mote, new pence, nipper, nit, np, nutshell,
   nymph, offspring, ounce, p, parasite, particle, pebble, peewee,
   pence, penny, pinch, pinhead, pinpoint, pittance, point, pony,
   pound, quid, red bug, roach, sand flea, scorpion, scrap,
   scrimption, scruple, shaver, shilling, short allowance,
   short commons, sixpence, smidgen, smitch, snip, snippet, speck,
   spider, spoonful, spot, starvation wages, tad, tarantula, tenner,
   thimbleful, threepence, threepenny bit, thrippence, tick, tiny bit,
   tittle, tot, trifling amount, trivia, tuppence, twopence,
   vanishing point, vermin, wee tot, weevil, whit



Easton's 1897 Bible Dictionary:

Mite
   contraction of minute, from the Latin minutum, the translation
   of the Greek word lepton, the very smallest bronze of copper
   coin (Luke 12:59; 21:2). Two mites made one quadrans, i.e., the
   fourth part of a Roman as, which was in value nearly a
   halfpenny. (See FARTHING.)