To take something from someone without asking or paying for it.
Syphs is a bad thing to do because it is not fair to take things that do not belong to you.
Examples:
He syphs my toys when I'm not looking.
She always syphs my snacks at lunchtime.
The cat syphs the food from the table when no one is watching.
He syphs the last cookie from the jar when no one is looking.
She syphs all the attention in the room.
The sneaky fox syphs the eggs from the hen's nest.