Is fondly a synonym for rarely?

No, "fondly" and "rarely" are not synonyms. They have completely different meanings.

* Fondly: Means with affection, love, or liking.

* Rarely: Means not often, infrequently.

Here are some examples:

* Fondly: "She fondly remembered her childhood summers."

* Rarely: "He rarely visits his family."

Let me know if you have any other word comparisons you'd like to explore!