If we're talking about the US, my understanding is that the term "sushi grade" is unregulated and generally used to identify fresher, higher quality fish. While it can mean that it was flash frozen, as many of these other posts indicate, it does not necessarily mean that it was and can be used as a marketing ploy.
However, confusingly, I have seen information saying that the FDA does have standards for fish the care of fish meant to be eaten raw, which include freezing it to specific temperatures for specific lengths of time to kill parasites.
SemiSigh12 t1_iu2ro4e wrote
Reply to ELI5: How come sushi is safe to eat but normal raw fish isn't? by Thylocine
If we're talking about the US, my understanding is that the term "sushi grade" is unregulated and generally used to identify fresher, higher quality fish. While it can mean that it was flash frozen, as many of these other posts indicate, it does not necessarily mean that it was and can be used as a marketing ploy.
However, confusingly, I have seen information saying that the FDA does have standards for fish the care of fish meant to be eaten raw, which include freezing it to specific temperatures for specific lengths of time to kill parasites.