How do you spell heavy plus er?

The correct spelling of "heavy plus er" depends on what you are trying to say.

Here are some possibilities:

* Heavier: This is the comparative form of "heavy" and means "more heavy."

* Heavier: This is the comparative form of "heavy" and means "more heavy." You could use it in a sentence like, "This rock is heavier than that one."

* Heavier: This is the comparative form of "heavy" and means "more heavy."

If you can provide more context, I can give you a more accurate answer.