Smith's Dictionary
(given) one of the sons of Bigvai, who returned in the second caravan with Ezra. (Ezra 8:14) (B.C. 459.)
International Standard Bible Encyclopedia
zab'-ud (zabbudh, meaning uncertain; Ezr 8:14, where Kere is zakkur and Kethibh is zabhudh = "Zabud"; 1 Esdras 8:40 has "Istalcarus"): A companion of Ezra on his journey from Babylon to Jerusalem.