Endearing describes something or someone extremely lovable, like a kitten or your friend's sense of humor.
The adjective endearing was originally used in the 1500s to mean "enhancing the value of," and by the 1640s it also meant "making dear or precious." It can still be used both ways, although the second meaning of endearing is most common. Any time you talk about a person or thing that's adorable or extremely likable, you can describe it as endearing.
