"Of the 23 elements in seven moving groups, seven are made from glasses with anomalous partial dispersion for the minimisation of chromatic aberrations. "
I looked it up. It's just another way of saying "Low-Dispersion" as compared with standard glass. Like Thoriated glass.
"This characteristic is known either as "extraordinary partial dispersion" or "anomalous dispersion" (in this article, the term "anomalous dispersion" will be used). Nikon has dubbed glass that possesses this characteristic "ED glass."