The Collaborative International Dictionary of English v.0.48:

Timidity \Ti*mid"i*ty\, n. [L. timiditas: cf. F. timidit['e].]
   The quality or state of being timid; timorousness; timidness.
   [1913 Webster]

WordNet (r) 3.0 (2006):

timidity
    n 1: fear of the unknown or unfamiliar or fear of making
         decisions [syn: timidity, timidness, timorousness]
    2: fearfulness in venturing into new and unknown places or
       activities [syn: timidity, timorousness] [ant:
       boldness, daring, hardihood, hardiness]

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "timidity":
   afraidness, bashfulness, chicken-liveredness, chickenheartedness,
   confusion, cowardice, cowardliness, coyness, demureness, demurity,
   diffidence, embarrassment, faintheart, faintheartedness, fear,
   fearfulness, henheartedness, jumpiness, lily-liveredness,
   milksopism, milksoppiness, milksoppishness, mousiness,
   pigeonheartedness, self-consciousness, shamefacedness,
   shamefastness, shrinkingness, shyness, skittishness, softness,
   stage fright, stagefright, stammering, startlishness, timidness,
   timorousness, unmanfulness, unmanliness, weakheartedness, weakness,
   yellowness