4 occurrences in 4 dictionaries
Reference: Rabsaris
Easton
Fausets
1. Sent by Sennacherib with Tartan and Rabshakeh against Jerusalem (2Ki 18:17). ("chief eunuch"), often a minister of state or a commander in expeditions (margin, 2Ki 25:19).
2. One of Nebuchadnezzar's princes at the taking of Jerusalem under Zedekiah (Jer 39:3,13); probably a title of Nebushasban, i.e. worshipper of Nebo. (See NEBUSHASBAN.)
Morish
Smith
Rab'saris
(chief of the eunuchs).
1. An officer of the king of Assyria sent up with Tartan and Rabshakeh against Jerusalem in the time of Hezekiah.
(B.C. 713.)
2. One of the princes of Nebuchadnezzar, who was present at the capture of Jerusalem, B.C. 588.
Rabsaris is probably rather the name of an office than of an individual.