Personal name of uncertain meaning, perhaps “island of palms,” or “where is Tamar,” or shortened form of “father of Tamar (palms).” Fourth son of Aaron the priest (Exod 6:23). After the death of Nadab and Abihu, Ithamar and his surviving brother Eleazar rose to prominence. During the wilderness years Ithamar apparently was in charge of all the Levites (Exod 38:21).

Moses became angry when Ithamar and his brother did not eat part of an offering as commanded (Lev 10:16). In addition, the house of Eli evidently was descended from Ithamar.