A likeness is a portrait, or a head-turning resemblance. George Washington’s likeness appears on the dollar bill. A potato might bear an uncanny likeness to my grandfather.
Likeness has nothing to do with liking someone or something––it’s all about what something looks like. It’s been in use since before the 12th century, when likenesses had to be drawn or painted, rather than snapped with a digital camera. If the only picture you had of your mom was one your brother drew, you would value it more if it was a good likeness, meaning it really looked “like” her.