Blunder
Mistake, error, goof, blunder, miscalculation, misstep.
Take care to not repeat this blunder. I was very embarrassed with my blunder.
"gaffe" "social blunder"; embarassed; inept; awkward; social boor.
I want to see Maxwell Smart's next blunder.
Blunder can be a noun and a verb. Noun: An embarrassing mistake. Verb: To make an embarrassing mistake.
The worker's blunder nearly drove his employers to bankruptcy.
A bad move in chess is called a "blunder".
blunder
It seems as though Great Britain's attempt to imperialize the world was a blunder.
a social blunder
a stupid or careless mistake