The answer depends on what expression you do have and for what kind of shape!
No kind: it is an expression, not an equation.
A numerical constant.
addition.
It is not a property of any kind. It is a muiltiplication expression.
A constant expression.
It isa linear expression,a binomial expression,an algebraic expression,a polynomial expression.
idiomatic expression
The answer depends on what expression you do have and for what kind of shape!
monomial
You forgot to tell us what the expression is. That's kind of important.
No kind: it is an expression, not an equation.
Add to it some kind of label to tell the directionof the speed.
Some kind of an algebraic expression
It is some kind of an algebraic expression
A numerical constant.
addition.