🔼The name Goiim in the Bible
It's not wholly clear whether Goiim (or Goyim), meaning nations (see below) is supposed to be a name or rather part of the narrative. The Septuagint, Vulgate and King James versions treated Goiim as part of the narrative but younger versions of the English Bible tend to go with Goiim as proper name.
We hear first of the name Goiim, if indeed it is one, at the onset of the War of Four Against Five kings, in which king Tidal of Goiim and three royal colleagues of certain established Mesopotamian kingdoms went to war with five Canaanite rivals (Genesis 14:1). Where exactly this king Tidal held his sway is no longer known. It might have been a place that sounded to the Hebrews as Goiim (nations) but it's also possible that Tidal himself represented a smaller sub-alliance of clans, which joined the larger alliance as one.
Something similar appears in the defeated-kings list of Joshua 12 in which the author gloats over the demise of an unnamed king of Goiim in Gilgal (Joshua 12:23). Again, this Goiim may have been an otherwise unmentioned city in Gilgal (east of the Salt Sea) but it may also have been a reference to a freshly established (pre-named) alliance of local tribes and clans.
Likewise, general Sisera of Harosheth-hagoyim (that is: Haroshet "of the nations") may in fact have been the kind of military figure that emerges naturally from the joining of forces of various otherwise unrelated nations (Judges 4:2) although the usages of this name in Judges 4:13 and 4:16 seem to suggest that this name was indeed associated with a specific geographical location.
🔼Etymology of the name Goiim
The name Goiim is a regular plural form of the masculine noun גוי (goy) meaning people or nation:
There are no two ways about it: the name Goiim means Nations and denotes the physical presence of peoples other than Israel.