hand·breadth 
(hăndbrĕdth′) also hand's-breadth or hand's breadth (hăndz-)
(hăndbrĕdth′) also hand's-breadth or hand's breadth (hăndz-)n.
A linear measurement approximating the width of the palm of the hand, from 2.5 to 4 inches (6.35 to 10.16 centimeters).