Zamzum'mim (Heb. Zamzummim', זִמזמַּים; Sept. Ζομζομμείν v.r. Ζοχομμίν, Vulg. Zomzommim, A.V. "Zamzummims"), the Ammonitish name for the people who by others (though who they were does not appear) were called Rephaim (q.v.) (De 2:20 only). They are described as having originally been a powerful and numerous nation of giants — "great, many, and tall" — inhabiting the district which at the time of the Hebrew conquest was in the possession of the Ammonites, by whom the Zamzummim had a long time previously been destroyed. Where this district was it is not, perhaps, possible exactly to define; but it probably lay in the neighborhood of Rabbath-Ammon (the present Amman), the only city of the Ammonites of which the name or situation is preserved to us, and therefore eastward of that rich undulating country from which Moab had been forced by the Amorites (the modern Belka), and of the numerous towns of that country whose ruins and names are still encountered.
From a slight similarity between the two names, and from the mention of the Emim in connection with each, it is usually assumed that the Zamzummim are identical with the Zuzim (q.v.) (Gesenius, Thesaur. p. 410 a; Ewald, Gesch. 1, 308, note; Knobel, On Genesis 14:5). Ewald further supports this by identifying Ham (q.v.), the capital city of the Zuzim (Ge 14:5), with Ammon. But at best the identification is very conjectural.
Various attempts have been made to explain the name: as, by comparison with the Arabic zamzam, "long-necked;" or samsam, "strong and big" (Simonis, Onomast. p. 135); or as "obstinate," from זָמִם (Luther), or as "noisy," from זַמזִם (Gesenius, Thesaur. p. 419), or as onomatopoetic, intended to imitate the unintelligible jabber of foreigners. Michaelis (Supplem. No. 629) playfully recalls the likeness of the name to that of the well Zen-zem at Mecca, and suggests thereupon that the tribe may have originally come from Southern Arabia. Notwithstanding this banter, however, he ends his article with the following discreet words, "Nihil historiae, nihil originis populi novirmus fas sit etymolo gium aeque ignorare." See Journ. Sac. Lit. 1852, p. 366.