Fidget (verb)

1. To make small, nervous movements, typically with one's hands or feet.
2. To be unable to sit still or keep still due to restlessness or nervousness.
3. To be unable to keep one's mind on something.

Origin:

Late 16th century (as a noun denoting a small device for occupying the hands): perhaps from dialect fidget "fidgeting, restlessness".

Examples:

1. He couldn't help but fidget during the long lecture.
2. She was fidgeting with her pen during the meeting.
3. He was fidgeting in his seat as he waited for the interview.
4. She fidgeted with her hair while she was on the phone.
5. He could not stop fidgeting, his nerves were getting the best of him.