Name for Design Pattern

I've previously used the term Decorator to refer to "a class which accepts a Foo data class, and returns a Foo which contains broadly the same attributes as the original Foo, with potentially some changes/additions to the data". However, since moving to a new team, I found that this term is apparently already associated with the Adapter pattern.

Are there any terms for the pattern I'm describing? We're currently deciding between "Annotator" or "Augmenter", neither of which inspires great loyalty. "Mutator" wouldn't really fit since (at least in this case) the intention is for the changes to be purely additive.