Facepalm
-The fact that you had to even ask me that makes me want to facepalm.
-Facepalm; some of these people in the world are just so stupid.
- It was so silly when you said that, a complete facepalm moment.
Meaning: A gesture in which the palm of one's hand is brought to one's face, as an expression of disbelief, shame, or exasperation.
Origin: According to Macmillan Dictionary, the word "facepalm" first appeared around 2006. Perhaps the most notorious example comes from the sci-fi series Star Trek: The Next Generation. An image of Jean-Luc Picard, played by Patrick Stewart, expressing frustration using this gesture has become a famous.
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Other examples:
1. Facepalm, my friend shared our conversation with her husband. It's about seeking my advice about how to fix their marriage.
2. It was a facepalm moment in the subway train when she started to sing so loudly; just like nobody was there!