Targum for Genesis 10:25

וּלְעֵ֥בֶר יֻלַּ֖ד שְׁנֵ֣י בָנִ֑ים שֵׁ֣ם הָֽאֶחָ֞ד פֶּ֗לֶג כִּ֤י בְיָמָיו֙ נִפְלְגָ֣ה הָאָ֔רֶץ וְשֵׁ֥ם אָחִ֖יו יָקְטָֽן׃

And unto Eber were born two sons; the name of the one was Peleg; for in his days was the earth divided; and his brother’s name was Joktan.

Targum Jonathan on Genesis