When Jerome was introduced to Sally, he realized that he had committed an embarrassing gaffe when he didn't pronounce her name correctly.
It would be an unprecedented social gaffe if Emmett were to try to gaff when playing cards; in fact, his opponent might think of using a metal gaff to stop him.
2. A blundering social error; a "faux pas": Trisha realized that she had committed an embarrassing gaffe when she mispronounced the name of the diplomat's wife during the introduction.
3. A blatant mistake or misjudgment: It is a serious gaffe to forget to lock one's house when he or she leaves home.
A White House gaffe irritated diplomats who were forced to cool their heels.
Several foreign diplomats were mistakenly denied entry to the White House when they arrived for an annual reception, and though most finally made it in, a few left in anger.