I'd say AST to AST translation is a transpiler. It keeps the high-level structure of the program intact. Once you break down the AST into basic blocks/CFG, the

I'd say AST to AST translation is a transpiler. It keeps the high-level structure of the program intact. Once you break down the AST into basic blocks/CFG, then you have a compiler (if the output is from the "lowered" representation that has lost its high-level shape).