investor

An investor is someone who provides (or invests) money or resources for an enterprise, such as a corporation, with the expectation of financial or other gain.

We usually hear about an investor in a business context, but when someone invests things like time or labor in a project or idea they, too, are investors of a sort. The "return on investment" in these cases, however, is often a little less tangible than money. Someone who volunteers to help build houses is an investor in their community. Someone who spends time helping a child with homework is an investor in that child's future.