Question 1

What does "under someone's thumb" mean?

Accepted Answer

Completely controlled or dominated by another person.

Question 2

How do you use "under someone's thumb" in a sentence?

Accepted Answer

Everyone knew he was completely under his manager's thumb.

Question 3

Is "under someone's thumb" formal or informal?

Accepted Answer

"under someone's thumb" is register-neutral — appropriate in both casual and formal contexts. Used to describe a power imbalance in a relationship or professional setting.