quaking/shaking in your boots/shoes
quake in (one's) boots
To tremble with fear. Often used sarcastically. My brother is so strong and scary-looking that people quake in their boots when he threatens them. Ooh, I'm really scared of you! I'm quaking in my boots, you frighten me so!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
(be) ˌquaking/ˌshaking in your ˈboots/ˈshoesbe very worried or frightened: The prospect of facing the team again in the semi-final had everyone quaking in their boots.
Farlex Partner Idioms Dictionary © Farlex 2017