To move quietly and secretly, especially because you are doing something you should not be doing.
Sneaked can make people think of being sneaky or doing something wrong.
Examples:
He sneaked into the kitchen to get a cookie.
She sneaked out of the house without telling anyone.
The cat sneaked up on the bird.
The mouse sneaked into the pantry and ate all the cheese.
The spy sneaked past the guards without them seeing.
I sneaked into the room and surprised my friend.