Entry 1 sense Webster, 1913 Entombment /ĭn-to͞om'-mənt/ · En·tomb·ment · IPA /ɪnˈtuːm.mənt/ 01 n. The act of entombing or burying, or state of being entombed; burial. 1. The act of entombing or burying, or state of being entombed; burial.