n. a color phase of the red fox, Vulpes ful, characterized by black fur having silvery-white guard hairs dispersed over the back, found rarely in nature but nowadays bred on fox farms.
1861  The "silver-hair" is the same size as our common fox, with a beautiful jet-black fur for the ground, which on each end is tagged with about an inch of "silver tinge," which glitters like jewels in the sun and snow.