A person who actively campaigns, agitates, or works against parliamentary government or parliamentary institutions.
From antiparliament + -eer (suffix for people involved in an activity, like auctioneer or profiteer). The -eer ending suggests active engagement and promotion of antiparliamentary views.
The term 'antiparliamenteer' has a somewhat dated quality, appearing mainly in early 20th-century political criticism describing fascists and communists who actively worked to overthrow parliaments.
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