What is…
Samgar-nebo

also known as: Samgar-nebu

Meaning: be gracious, O Nebo! or a cup-bearer of Nebo

This is probably the title of Nergal-sharezer, one of the princes of Babylon.

Then all the officials of the king of Babylon came in and sat down at the Middle Gate: Nergal-sar-ezer, Samgar-nebu, Sar-sekim the Rab-saris, Nergal-sar-ezer the Rab-mag, and all the rest of the officials of the king of Babylon. —Jeremiah 39:3