(n.) A contemptible or vicious critic.

Sunday painter abecedarian admirer aesthete aficionado amateurish apprentice arbiter arbiter elegantiarum arbiter of taste authority avocational beginner bon vivant booster buff bungler bungling clumsy cognoscente collector connaisseur connoisseur coquet crank critic criticaster crude dabbler dabbling dabster dallier devotee dilettante dilettantish enthusiast epicure epicurean expert faddist fan fancier flirt follower freak fribble good judge gourmand gourmet grammaticaster greenhorn groupie half scholar half-assed half-baked half-cocked idolater idolizer immature inexpert infatuate inferior judge lay layman maven mediocre neophyte nonprofessional novice nut philologaster philosophaster piddler potterer probationer pundit putterer refined palate rooter savant scholar sciolist sciolistic second-rate shallow smatterer smattering sophomoric specialist superficial technical expert technician tinker trifler tyro unpaid unprofessional unskilled untrained virtuoso votary worshiper zealot