wriggler

from WordNet (r) 3.0 (2006)

wriggler
    n 1: one who can't stay still (especially a child); "the toddler
         was a real wiggler on plane trips" [syn: {wiggler},
         {wriggler}, {squirmer}]
    2: larva of a mosquito [syn: {wiggler}, {wriggler}]

from The Collaborative International Dictionary of English v.0.48

Wriggler \Wrig"gler\, n.
   One who, or that which, wriggles. --Cowper.
   [1913 Webster]