under one's thumb

[under one's thumb] or [under the thumb] {adj.} or {adv. phr.}Obedient to you; controlled by you; under your power.

The Jonesfamily is under the thumb of the mother.

Jack is a bully. He keepsall the younger children under his thumb.

The mayor is so popularthat he has the whole town under his thumb.

Compare: JUMP THROUGH THEHOOP.