gaffe or (rare) gaff /gaf/

A blunder

• nondescript
• nondescriptly
• nondescriptness
• nondescriptnesses
• nondescripts
• non-destructive
• non-destructive testing
• non-disciplinary
• non-discriminating
• nondisjunction
• nondisjunctions
• non-dividing
• non-divisible
• non-dom
• non-doms
• non-drinker
• non-drinkers
• non-drip
• non-driver
• non-drivers
• none
• non-economic
• non-effective
• non-effectives
• non-efficient