|Easton's Bible Dictionary|
(1.) Ishmael's eldest son (Genesis 25:13), and the prince of an Israelitish tribe (16). He had a sister, Mahalath, who was one of Esau's wives (Genesis 28:9; 36:3).
(2.) The name of the Ishmaelite tribe descended from the above (Genesis 25:13, 18). The "rams of Nebaioth" (Isaiah 60:7) are the gifts which these wandering tribes of the desert would consecrate to God.
Int. Standard Bible Encyclopedia
ne-ba'-yoth, ne-bi'-oth (nabhayoth; Septuagint Nabaioth): Firstborn of Ishmael (Genesis 25:13; Genesis 28:9; Genesis 36:3 1 Chronicles 1:29). Isaiah 60:7 mentions the tribe Nebaioth with Kedar, with an allusion to its pastoral nature: "the rams of Nebaioth" are to serve the ideal Zion as sacrificial victims. Again associated with Kedar, the name occurs frequently in Assyrian inscriptions. The tribe must have had a conspicuous place among the northern Arabs. Josephus, followed by Jerome, regarded Nebaioth as identical with the Nabateans, the great trading community and ally of Rome, whose capital and stronghold was Petra. This view is widely accepted, but the name "Nabatean" is spelled with a "T" (teth), and the interchange of "T" (teth) and "t" (taw), although not unparalleled, is unusual. If the name is Arabic, it is probably a feminine plural, and in that ease could have no connection with the Nabateans.
A. S. Fulton
Nebaioth (5 Occurrences)
Genesis 25:13 These are the names of the sons of Ishmael, by their names, according to the order of their birth: the firstborn of Ishmael, Nebaioth, then Kedar, Adbeel, Mibsam, (WEB JPS ASV BBE DBY NAS NIV)
Genesis 28:9 Esau went to Ishmael, and took, besides the wives that he had, Mahalath the daughter of Ishmael, Abraham's son, the sister of Nebaioth, to be his wife. (WEB JPS ASV BBE DBY NAS NIV)
Genesis 36:3 and Basemath, Ishmael's daughter, sister of Nebaioth. (WEB JPS ASV BBE DBY NAS NIV)
1 Chronicles 1:29 These are their generations: the firstborn of Ishmael, Nebaioth; then Kedar, and Adbeel, and Mibsam, (WEB KJV JPS ASV BBE DBY WBS YLT NAS NIV)
Isaiah 60:7 All the flocks of Kedar shall be gathered together to you, the rams of Nebaioth shall minister to you; they shall come up with acceptance on my altar; and I will glorify the house of my glory. (WEB KJV JPS ASV BBE DBY WBS YLT NAS NIV)