Terminology for a weaked vector space

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Let $S$ be a semigroup on which acts $\mathbb{R}_{\geq0}$. Does this structure has a name?

For example $S$ can be the set of convex bodies in $\mathbb{R}^n$ with the Minkowsky sum.

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Assuming you want the semigroup to be commutative (as it is for Minkowski sum), such an object is called a convex cone.

Added: When if it's not naturally sitting in a vector space, one can avoid confusion by calling the object an abstract convex cone. For example, Wikipedia talks about

(abstract) convex cone of nonempty compact convex sets