silver vixen

Modelled on earlier silver fox.

silver vixen (plural silver vixens)

1. A female silver fox (animal).
   • 1968, The foxes of Beachy Cove, page 25:

     I saw a very dark silver fox slip across the road just in front of me. After a while I discovered that they were a mated pair—the biscuit-colored dog fox and the smaller silver vixen.

2. (colloquial) An attractive woman who has graying hair.