The following words, terms, and phrases, when used in this article, shall have the meanings ascribed to them in this section, except where the context clearly indicates a different meaning:
Any privately owned man-made depression in the ground, either temporary or permanent, in which water more than 18 inches is contained.
Any depression in the ground, either temporary or permanent, or a container of water, either temporary or permanent and either above or below the ground, in which water more than 18 inches deep is contained and which is used primarily for the purpose of bathing or swimming.