What do you call folks that are third cousins two different ways?

Question

I've come across two third cousins, who are third cousins through two different routes as the same two families had two separate marriages between them that leads to this situation.

I was thinking perhaps calling them double third cousins, but would like to know the official terminology.

You can see an example of this relationship here. Notice that there are two sets of married ancestors, the Brown/Hodges marriage and the Brizendine/Cochran marriage, both common relations make them third cousins. See popup menu that allows navigation among the four common ancestors in this screenshot:

Answer 1

I think that you are using the correct term of double third cousins.

Two individuals are third cousins when they share a single pair of 2nd great grandparents.

Since your individuals share two pairs of 2nd great grandparents they are double third cousins.

From "Genetic and Quantitative Aspects of Genealogy" (F. M. Lancaster; Oct 2005, updated Feb 2015) I learned that:

there are 9 possible kinds of double third cousins

From my quick look at that paper it seems like there are many relationships possible, but fortunately for this one the simple term of double third cousins is available.