countersniper

noun

coun·​ter·​snip·​er ˌkau̇n-tər-ˈsnī-pər 

variants or counter-sniper

plural countersnipers or counter-snipers

: a sniper employed to target and attack enemy snipers

He had been a countersniper for the security details assigned to protect Hamid Karzai in Afghanistan and Paul Bremer, the former American proconsul, in Iraq.

—Tom Junod

Word History

First Known Use

1942, in the meaning defined above