Then just define them! The entire subject is about linear transformations on vector spaces. The biggest problem with linear algebra as its taught today is that

Then just define them! The entire subject is about linear transformations on vector spaces. The biggest problem with linear algebra as its taught today is that students uniformly come out with an understanding that linear algebra is about matrices. It should be made clear that a matrix is simply a representation of a transformation, and then when you do teach the grunt work operations, you can teach them as what they actually are (multiplication: composition of transformations, determinant: area of unit square under transformation, etc.)