gaffe or (rare) gaff /gaf/

A blunder

• omnipotency
• omnipotent
• omnipotently
• omnipresence
• omnipresences
• omnipresent
• omnirange
• omniranges
• omniscience
• omnisciences
• omniscient
• omnisciently
• omnishambles
• omnium
• omnium-gatherum
• omnium-gatherums
• omniums
• omnivore
• omnivores
• omnivories
• omnivorous
• omnivorously
• omnivorousness
• omnivory
• omohyoid