Strong's Definition
from 2161; intriguing; a Zamzumite, or native tribe of Palestine
KJV Usage: Zamzummim
STEPBible — Tyndale Abridged Hebrew Lexicon
זַמְזֻמִּים (zam.zom) — Zamzummin. People descended from Repha(?), first mentioned at Gen.14.5 Another name of re.pha.im (רְפָאִים "Rephaim" H7497B) § Zamzummims = "plotters" the Ammonite name for the people who by others were called Rephaim, and were described as a numerous nation of giants; perhaps the same as 'Zuzim'
UBS Dictionary of Biblical Hebrew
name
Names of Groups | ≈ רְפָּאִים
Zamzummites = ethnic group, possibly to be identified with the Zuzim and also known as Rephaites; ◄ located in Ammon
UBS Dictionary of Biblical Hebrew © United Bible Societies, licensed CC BY-SA 4.0.
Brown-Driver-Briggs Hebrew Lexicon
זַמְזֻמִּים n.pr.gent. said to be a name given to רְפָאִים by the Ammonites who dispossessed them Dt 2:20 ref