WTF is Variegate?

So, I was eating some Mayfield Peanut Butter Cookie Dough Ice Cream. I read the little description thinggie and it described it as "Cookie dough-flavored ice cream with a peanut butter variegate and cookie dough pieces."

I got to wondering -- first, what is a variegate. Then wondering who in Athens, TN knows what a variegate is.

I don't fathom myself as having an extensive vocabulary. In fact, I know I use words incorrectly left and right. But, generally I like to think I've heard of words that are on my food (outside of the monosodium glutimate and such in the ingredients). If you're going to describe a food, use ordinary words.

So I went to dictionary.com and looked up variegate and found this:

variegate Pronunciation Key (vair-ee-i-geyt, vair-i-geyt)
tr.v. variegated, variegating, variegates

1. To change the appearance of, especially by marking with different colors; streak.
2. To give variety to; make varied.

I'm confused first because dictionary.com references it as a verb, and it's used as a noun in the description. Then I'm even more confused as to why they didn't say "a peanut butter swirl."

Maybe Mayfield thinks their target audience is much more intelligent than me. I'm pondering on partaking in the purchasing of their products after this post.