Another interesting look into etymology!
Grieving Widow. A saddened woman mourning the recent death of her husband.
From ancient Etruscan times to the 18th century, soldiers wore protective leather or cloth leggings called "greaves." When soldiers died in battle, their widows back home then earned their living cutting and sewing greaves for other soldiers. They became known as "greaving widows," which later evolved into "grieving widows."
(Information provided by “The Complete Footwear Dictionary: Second Edition” by Dr. William A. Rossi, 2000.)