The Posuk Says(25,22):

שְׁנֵי [גיים] גוֹיִם בְּבִטְנֵךְ וּשְׁנֵי לְאֻמִּים מִמֵּעַיִךְ יִפָּרֵדוּ

Translated as: Two nations are in your womb, and two kingdoms will separate from your innards

What is the diffrence between a גוֹיִם and a לְאֻמִּים