King James Bible Dictionary

Called also Geshem, a Samaritan.
Nehemiah 6:1; Nehemiah 6:6

Or Gashmu, firmness, probably chief of the Arabs south of Palestine, one of the enemies of the Jews after the return from Babylon (Nehemiah 2:19; 6:1, 2). He united with Sanballat and Tobiah in opposing the rebuilding of the wall of Jerusalem.

Called also Gashmu, an Arabian. Opposed Nehemiah in building Jerusalem.
Nehemiah 2:19; Nehemiah 6:1-6

and Gash'mu (rain), an Arabian, mentioned in (Nehemiah 2:19) and Nehemiah 6:1,2,6 (B.C. 446.) We may conclude that he was an inhabitant of Arabia Petr'a or of the Arabian desert, and probably the chief of a tribe." Gashum said it" made him a type of those who create a common report.