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bolt from the blue, a

Also, a bolt out of the blue. A sudden, unexpected event. For example, Bill's dropping his life insurance was a bolt from the blue for his wife. This metaphoric term alludes to totally unforeseen lightning or thunder from a cloudless (blue) sky. [First half of 1800s]

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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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The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.