🔼The name Zuzim in the Bible
The name Zuzim occurs only once in the Bible. It denotes a people who lived in a place called Ham, and who were defeated by kings Amraphel, Arioch, Chedorlaomer and Tidal, just prior to the War of Four Against Five Kings (Genesis 14:5). Because the tetrad alliance also defeated the Rephaim and the Emim, both races of giants, it's often supposed that the Zuzim were giants too. And in that case the Zuzim could be the same as the Zamzummim, who were giants indeed and even the same as the Rephaim (Deuteronomy 2:20).
However, the list of peoples defeated by Chedorlaomer goes on to include the Horites, the Amalekites and the Amorites, who surely weren't giants or else we would have heard about it. And just because both the names Zuzim and Zamzummim have two z's in them, doesn't make them the same. In fact, they are quite unlike.
Ergo: the Zuzim may have been giants but we have no reason to assume that they were.
🔼Etymology of the name Zuzim
The name Zuzim is a plural form derived of either root זוז:
For a meaning of the name Zuzim, NOBSE Study Bible Name List reads Prominent, Giant, which can not possibly be tied into either of the roots זוז. Jones' Dictionary of Old Testament Proper Names goes with זוז I, and interprets our name with the rather liberal Commotions, "i.e. terrors". BDB Theological Dictionary doesn't interpret our name but lists it under the root זוז II. Following BDB, the name Zuzim would mean something like The Many or Lavish Ones.