built-in /ˈbɪltɪn/adjective 3noun 2forms 1 adjective3 •Constructed as a nondetachable part of a larger structure. •Being an essential and permanent part of something. •Being an included feature that normally comes as an extra. noun2 •Anything (such as a piece of furniture, or a software feature) that is built in, not added as an extra.Still, some commenters were quick to criticize the trend, arguing that bookshelf wealth simply indicates you have the financial means (and the space for a built-in) and that it can lean inauthentic. — 2024 •A function that is built into a system. formsbuilt-ins