As used in this article, the following terms shall have the meanings indicated:
A structure or lot that does not conform to a dimensional regulation prescribed by this chapter for the district in which it is located or to regulations for signs, off-street parking, off-street loading, or accessory buildings, but which structure or lot was in existence at the effective date of this chapter and was lawful at the time it was established.
A use of a building or lot that does not conform to a use regulation prescribed by this chapter for the district in which it is located, but which was in existence at the effective date of this chapter, was lawful at the time it was established, and is duly recorded under the provisions of § 465-64.