faux pas
noun
[ fəʊ ˈpɑː ]
• an embarrassing or tactless act or remark in a social situation.
• "‘I was suddenly sick in the back of their car’—it was years before he could confess his faux pas to them"
Similar:
gaffe,
blunder,
mistake,
indiscretion,
impropriety,
breach/lapse of etiquette,
solecism,
gaucherie,
peccadillo,
boo-boo,
slip-up,
howler,
boner,
boob,
clanger,
blooper,
bloomer,
Origin:
French, literally ‘false step’.