To squirm means to move around a lot, especially when you are uncomfortable or trying to get away from something.
Squirming can make people think of being uncomfortable, like when you don't want to sit still.
Examples:
The little boy started to squirm in his seat.
She squirmed out of her mother's grasp.
The worm squirmed in the dirt.
The cat tried to squirm out of the bath.
I squirm when I have to sit still for a long time.
The fish squirmed and splashed in the net.