Entry 1 sense Webster, 1913 Derringer /dĕr'-ən-jẽr/ · Der·rin·ger · IPA /ˈdɛɹɪndʒə(ɹ)/ 01 n. A kind of short-barreled pocket pistol, of very large caliber, often carrying a half-ounce ball. 1. A kind of short-barreled pocket pistol, of very large caliber, often carrying a half-ounce ball.