Assir (אַסִּיר) is a proper name meaning "prisoner" or "captive." It was borne by several persons in the Old Testament: a son of Korah (Exodus 6:24), a son of Ebiasaph (1 Chronicles 6:23), and a grandson of Jeconiah the king (1 Chronicles 3:17). The name reflects the difficult circumstances at the time of birth or perhaps a theological naming practice.
The Assir who was a son of Korah is particularly notable given the dramatic judgment on Korah's rebellion (Numbers 16). Yet God preserved Korah's line — "The sons of Korah, however, did not die" (Numbers 26:11). From this line came the sons of Korah who authored some of the most beloved psalms (Psalms 42–49, 84–85, 87–88). Even families marked by rebellion and names meaning "prisoner" can become vessels of worship and praise. God transforms the prisoner into the psalmist.