The Collaborative International Dictionary of English v.0.48:

Wriggle \Wrig"gle\, v. i. [imp. & p. p. Wriggled; p. pr. & vb.
   n. Wriggling.] [Freq. of wrig, probably from OE. wrikken to
   move to and fro; cf. LG. wriggeln, D. wrikken, Sw. vricka,
   Dan. vrikke.]
   To move the body to and fro with short, writhing motions,
   like a worm; to squirm; to twist uneasily or quickly about.
   [1913 Webster]

         Both he and successors would often wriggle in their
         seats,
         as long as the cushion lasted.           --Swift.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wriggle \Wrig"gle\, v. t.
   To move with short, quick contortions; to move by twisting
   and squirming; like a worm.
   [1913 Webster]

         Covetousness will wriggle itself out at a small hole.
                                                  --Fuller.
   [1913 Webster]

         Wriggling his body to recover
         His seat, and cast his right leg over.   --Hudibras.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wriggle \Wrig"gle\, a.
   Wriggling; frisky; pliant; flexible. [Obs.] "Their wriggle
   tails." --Spenser.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wriggle \Wrig"gle\, n.
   Act of wriggling; a short or quick writhing motion or
   contortion.
   [Webster 1913 Suppl.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

wriggle
    n 1: the act of wiggling [syn: wiggle, wriggle, squirm]
    v 1: to move in a twisting or contorted motion, (especially when
         struggling); "The prisoner writhed in discomfort"; "The
         child tried to wriggle free from his aunt's embrace" [syn:
         writhe, wrestle, wriggle, worm, squirm, twist]