lose one's nerve

lose (one's) nerve

To no longer have the courage to do something. I did want to ride the roller coaster earlier, but I'm starting to lose my nerve now that we're actually here.
See also: lose, nerve
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

lose one's nerve

Become frightened or timid, lose courage. For example, I wanted to ski down the expert slope but then I lost my nerve. This expression employs nerve in the sense of "courage or boldness." [Early 1900s]
See also: lose, nerve
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
Governing does cause stress and is a challenge but that does not mean that one should lose one's nerve and start looking for scapegoats to cover one's failures.