to move to and fro with short writhing motions; to squirm
to move or advance by twisting and turning
(usu + out of) to extricate or insinuate oneself by manoeuvring, equivocation, etc or ingratiation
The minister managed to wriggle out of a difficult question
to cause (a body part) to wriggle
She wriggled her hips
wriggler noun
[Middle English wrigglen from early Low German wriggeln]