(
Zero 
Knowledge 
Ethereum 
Virtual 
Machine)  A Layer 2 blockchain that supports Ethereum's virtual machine, the software that executes smart contracts.  zkEVMs therefore have the same functionality as Ethereum.
Examples of SNARK-based zkEVMs are Scroll and zkSync.  StarkNet is STARK-based and Polygon zkEVM is both SNARK and STARK.  See 
Layer 2 blockchain, 
EVM and 
zero-knowledge proof.