Peleg

PELEG (pē'lĕg, Heb. pelegh, division). One of the sons of Eber, brother of Joktan and the father of Reu (Gen.10.25; Gen.11.16-Gen.11.19; 1Chr.1.25). The reason for his being named Peleg is that “in his time the earth was divided.” This probably refers to the confounding of the language and the consequent scattering of the descendants of Noah (Gen.11.1-Gen.11.9).

International Standard Bible Encyclopedia (1915)

A son of Eber, and brother of Joktan. The derivation of the name is given: "for in his days was the earth divided" (niphleghah) (Ge 10:25; compare Lu 3:35, the King James Version "Phalec"). This probably refers to the scattering of the world’s population and the confounding of its language recorded in Ge 11:1-9. In Aramaic pelagh and Arabic phalaj mean "division"; in Hebrew pelegh means "watercourse." The name may really be due to the occupation by this people of some well-watered (furrowed), district (e.g. in Babylonia), for these patronymics represent races, and the derivation in Ge 10:25 is a later editor’s remark.