But that's not how definitions work. A definition is supposed to provide necessary and sufficient conditions for predicate application. As such, a definition can be either too wide, i.e. they can include things that aren't really the thing in question; or they can be too narrow, i.e. they can leave out things that are the thing in question.
Originally Posted by kb244
You defined pornography as something involving penetration. I cited an example of something that is not necessarily pornographic but does involve penetration. Hence your definition is too broad.