Years ago a neighbor had a round-fruited avocado, too.

Very probably a seedling tree that someone started as a lark, then figured "I might as will plant this."

I was talking to someone recently that said there is a new disease that hit the avos in the area that makes the fruit round. Wonder if that is it.

Most avos start out round...and then they can either change shape or stay the same. It is impossible to know what variety that is. After the fruit is full matured you can make an educated guess.

There is a round avo but for the life of me, I can't remember what it is. Dave Wilson Nursery does a 2 part youtube video on UC Irvines avocado repository and they talk about that round avocado.

Reed has round shape, and supposedly a very good tasting avocado.