(1):

(v. t.) To move with short, quick contortions; to move by twisting and squirming; like a worm.

(2):

(n.) Act of wriggling; a short or quick writhing motion or contortion.

(3):

(v. i.) To move the body to and fro with short, writhing motions, like a worm; to squirm; to twist uneasily or quickly about.

(4):

(a.) Wriggling; frisky; pliant; flexible.