quisler means synonym of quisling.
Etymology
Action noun from quisle + -er, in which the verb is a back-formation of the noun quisling – originally a proper noun – construed as a gerund or present participle.
noun
- Synonym of quisling.“Other potential "quislers" still at large last week include: Sweden's Sven Olav Lindholm, an Army sergeant who willingly dubs himself Sweden's Hitler; Holland's Blackshirt Anton Adrian Missert; Hungary's Greenshirt Kalman Hubay; England's Blackshirt Sir Oswald Mosley; Belgium's broom-waving Rexist Léon Degrelle and the underground pro-Nazi conspirators who agitate in Alsace-Lorraine.”