gaffe or (rare) gaff /gaf/

A blunder

• antivenenes
• antivenin
• antivenins
• antiviral
• antivirus
• antivitamin
• antivitamins
• antivivisection
• antivivisectionism
• antivivisectionist
• antivivisectionists
• antiwar
• antler
• antlered
• antler-moth
• antler-moths
• antlers
• antlia
• antliae
• antliate
• antlion
• antlions
• antoniniani
• antoninianus
• antonomasia