1built╟in pronunciation: function: adjective date: 1898 1 a : forming an integral part of a structure or object lt;a camera with a built╟in flashgt;; especially : constructed as or in a recess in a wall lt;a built╟in bookshelfgt; b : built into the ground lt;a built╟in swimming poolgt;2 a : inherent lt;a built╟in advantagegt; b : already established lt;her best-seller status gave her a built╟in audiencegt;