Entry 2 senses · 2 variants Webster, 1913 Boaster · Boast·er · IPA /ˈboʊstɚ/ n. n. 01 n. One who boasts; a braggart. 1. One who boasts; a braggart. 02 n. A stone mason's broad-faced chisel. 1. A stone mason's broad-faced chisel.