There is no direct equivalent unit for Monero (XMR) called a "satoshi" or "sat." The term satoshi specifically refers to the smallest indivisible unit of Bitcoin (BTC), where 1 BTC = 100,000,000 satoshis.
Monero uses a different divisibility standard:
1 XMR = 12 decimal places (unlike Bitcoin's 8).
The smallest unit of Monero is often referred to as a piconero (10^-12 XMR), analogous to how a satoshi is 10^-8 BTC.