How much is one blur?

Excuse me, I'm a bit new to the cryptocurrency world and I've encountered the term "blur" recently. Could you possibly clarify for me what it refers to and how much it typically equates to in monetary value? I've searched online but the information seems quite scattered. Is "blur" a unit of measurement for a specific cryptocurrency or does it have a broader meaning? Also, is there a standard exchange rate for "blur" against major currencies like the US dollar or Bitcoin? Any guidance you could provide would be greatly appreciated.