Definitions for quislingˈkwɪz lɪŋ
Random House Webster's College Dictionary
a person who betrays his or her country by aiding an invading enemy, often serving later in a puppet government.
Origin of quisling:
1940; after Vidkun Quisling (1887–1945), pro-Nazi Norwegian leader
collaborator, collaborationist, quisling(noun)
someone who collaborates with an enemy occupying force
A traitor who collaborates with the enemy.
Origin: 1940, after Vidkun Quisling (1887–1945), who ruled the Nazi collaborationist government of Norway during World War Two. Romanization of the Danish place name Kvislemark.