lowercase UK /ˌləʊ.ə(ɹ)ˈkeɪs/US /ˈloʊ.ɚˌkeɪs/adjective 1verb 1forms 3 adjective1 •In lower case.At a 1903 typography conference, attendees decided that they would use lowercase eszett and substitute “SZ” for uppercase instances of the letter, until they could figure out a proper design for it. — 2017 verb1 •To convert (text) to lower case.I never asked Rob e. Hanson why he lowercased his middle initial; I suppose he figured a man just shouldn’t accumulate too much capital. — 2000 formslowercased · lowercasing · lowercases