An investor is a person that allocates capital with the expectation of a future financial return or to gain an advantage. Through this allocated capital most of the time the investor purchases some species of property.

To invest is to allocate money with the expectation of a positive benefit/return in the future. In other words, to invest means owning an asset or an item with the goal of generating income

Stock is all of the shares into which ownership of a corporation is divided. In American English, the shares are collectively known as "stock".