What in the World is a Grex?

[camille1585]

The most embarassing thing is that I studied horticulture in my first 2 years of college, but after a good night sleep I'm going 'duh, you're right', cultivar is the name between apostrophes. But that still begs the question of why I have never heard of the word grex until I got into orchids?? I don't recall any instance of it being used for other plants...

I guess I got confused since many commercial cultivar names of horticultural crops don't include the apostrophes, making it read as a hybrid name.