To nudge something is to move it a little bit. You can also nudge a person.
The cat nudged the plate and it fell to the floor.
Give the machine a nudge and it’ll start working again.
You’ve got to give it a nudge. (This expression is often used with machines when they don’t work.)
The line of people waiting at airport security nudged slowly forward.
My dog nudges me with her head when she wants attention.
Sarah’s parents nudged her towards college. She was thinking about entering the military.
A dog will give you a nudge when it wants something.
If something doesn’t move at all, despite enormous effort and force applied to the object, then we often use the verb "budge" instead of "nudge." Notice also that "budge" is usually used with a negative word:
The car won’t budge.
This rusty nut won’t budge.
The members of Congress opposed to the legislation won’t budge. They refuse to change their position.