Mastemah appears as a noun meaning ‘hostility’ in OT (Hos. 9.7–8) and Qumran writings. In Qumran literature the word is mostly connected with an evil angel (Belial) and in Jub. Mastemah is always a proper name for the leader of the evil angels.
Maśṭēmâ originates from the Hebrew root śṭm, a by-form of śṭn (Wanke 1976: 821–822; [Satan] cf. the noun שׂטמה in 1QM. 14:9), and occurs also in Ethiopic. It is probable that the semantic evolution of Mastemah is like that of ʾAbaddôn: a noun for…