Noun
someone who collaborates with an enemy occupying force
Source: WordNetAfter the war collaborationist behaviour was popularly viewed as a result of mental deficiency, leaving the personality of the clearly more intelligent Quisling an "enigma". Source: Internet
He was offered freedom on the condition that he would serve as editor of a collaborationist Přítomnost; he refused and spent the whole of the war in Buchenwald. Source: Internet
Japanese Korea conscripted 2.6 million forced laborers controlled with a collaborationist Korean police force; some 723,000 people were sent to work in the overseas empire and in metropolitan Japan. Source: Internet