brassard
noun
bras·sard brə-ˈsärd 
ˈbra-ˌsärd
ˈbra-ˌsärd 1
: armor for protecting the arm see armor illustration
2
: a cloth band worn around the upper arm usually bearing an identifying mark
Word History
Etymology
French brassard, from Middle French brassal, from Old Italian bracciale, from braccio arm, from Latin bracchium — more at brace entry 2
First Known Use
1830, in the meaning defined at sense 1