not bat an eye

not bat an eye

To not display even a hint of an emotional response, such as consternation, annoyance, sadness, joy, etc. Mary didn't even bat an eye when I told her I was moving out. That guy is dangerous. I heard he killed a man without batting an eye.
See also: bat, eye, not
Farlex Dictionary of Idioms.

not bat an eye

mainly AMERICAN
If someone does not bat an eye when something happens, they do not appear at all shocked or surprised by it. She never batted an eye when I told her I was leaving my job. These people don't bat an eye when they're charged 16 dollars a pound for cheese. Note: You can also say that someone does something without batting an eye. He handed over the money without batting an eye. Note: The usual British expression is not bat an eyelid. Note: Bat is from a French word meaning to beat or flutter and is used of a bird's wings. The idea is that people who do not blink a lot in a given situation appear calm rather than nervous or surprised.
See also: bat, eye, not
Collins COBUILD Idioms Dictionary, 3rd ed.

not bat an eye

/eyelash Informal
To show no emotion; appear unaffected: The reporter didn't bat an eyelash while reading the gruesome news.
See also: bat, eye, not
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • even as
  • Don't even look like
  • don't even look like (something)
  • even then
  • a dead clock is correct twice a day
  • a dead clock is right twice a day
  • a stopped clock is right twice a day
  • correct
  • even now
  • even now/then
References in periodicals archive
He did not bat an eye, whereupon I said, 'Aren't you going to smile?' 'We're not allowed to,' he replied!
Straight to the point
"When I wished to place my Asian Buddha next to Mexican jugs, Cheryl did not bat an eye," laughs Mullen.
Before & after: if it made her happy, Abita Mullen included it in her decor
The day will come in this country when people will not bat an eye at gay and lesbian marriage.
LETTERS IN THE EDITOR'S MAILBAG
When Delaware Secretary of Education Valerie Woodruff first heard about her colleague's activities, she did not bat an eye.
Mentoring's biggest fan: one-on-one work helps this superintendent focus on his students--all 5,700 of them
I mean, you could sit David next to Sophia Loren and he would not bat an eye lid, but Paul Young, that's a different story!
Alison's Diary
The women in the audience did not bat an eye. But some reporter there from the New York Post picked it up, challenged the Ferrer people with it, and printed it the next day.
Dressed for surveillance. (Unplugged)