Galacto- and lacto- (galact/orrhea; lact/ase) mean:

This both means milk. In the medical term actually means spontaneous discharge of milk from the breast. Although frequently benign, it may be caused by serious underlying conditions and should be properly investigated. Galactorrhea is informed to occur in 5–32% of women. Much of the difference in reported incidence can be attributed to different definitions of galactorrhea.

I think they used the "real-world application" of math is that they used the real-world way of doing math and they created their own way of doing math.