Immar is an Aramaic noun meaning lamb, used specifically in the context of sacrificial animals required for temple worship. It appears in the Aramaic portions of Ezra describing the supplies requisitioned by the Persian king Artaxerxes for the restored worship in Jerusalem.
The lamb has profound theological significance throughout Scripture — from Abraham and Isaac on Moriah, through the Passover lamb of Exodus, to the Lamb of God who takes away the sin of the world (John 1:29). Even in Aramaic temple records, the lamb points forward to the ultimate sacrifice. Every temple lamb was a shadow of Christ.