To wiggle is to move something back and forth. When you dance, you probably wiggle your hips. If you wiggle them too much, your mother might wiggle a finger at you and say "Settle down!"
Young children wiggle loose teeth until they fall out. Sometimes, if your mom is trying to hold your little brother still, he'll wiggle out of her grasp and run off. Have you ever come across a rule that you don't want to follow? If so, you've probably tried to find some wiggle room, or little ways you could get out of doing what you don't want to do.