0 (of a person) never thinking about things that are serious or important: --
He's fun to be with, but he's very superficial.
1 not complete and involving only the most obvious things: --
2 appearing to be real or important when this is not true or correct: --
There are superficial similarities between the two cars, but really they're very different in terms of performance.
3 only on the surface of something: --
5 slight; not much: --