1. touch someone with the intention of doing harm
I never laid a finger on him/her!
The expression to 'lay a finger on' someone means to touch or hit someone with the intention of causing physical harm. To 'lay a hand on someone' has a similar meaning to grab or physically touch someone in order to hurt them or to cause violence. To 'lay your hands on something' means to obtain something or to find an object you've been looking for.