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out of a clear blue sky

Also, out of the blue. Without warning, suddenly, as in Her offer to help us with the fundraising came out of a clear blue sky, or We got a check from Aunt Ruby out of the blue. These metaphoric terms allude to something dropping unexpectedly from the sky. [Late 1800s] Also see out of nowhere.

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Question 1 of 9
You may have read the word "simmer" in a recipe or two, but what does it really mean?
To cook in water that begins cold and then reaches a boil.
To stew in a sauce for a long time.
To cook in water, just below boiling temperature.
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Words nearby out of a clear blue sky

outmoded, outmost, outmuscle, outness, outnumber, out of a clear blue sky, out-of-body, out-of-body experience, out-of-bounds, out of breath, out of business
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.