IPA: /ˈskwɜːrmər/
KK: /ˈskwɜrmər/
A person or thing that moves in a twisting or wriggling manner.
The little boy was a squirmer during the long meeting, unable to sit still.
Squirmer → It is formed from "squirm" (of uncertain origin, possibly imitative of the movement) and "-er" (meaning a person who). A squirmer is a person who squirms or wriggles, often in discomfort or nervousness.
Think of someone who is 'wriggling' or 'moving uncomfortably' — that's what a squirmer does.