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not breathe a word

Not reveal a secret, keep concealed, as in You must promise not to breathe a word of what I'm about to tell you. This phrase relies on the verb breathe as meaning “to utter,” a usage dating from the late 1500s.

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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 not breathe a word

notation, not bad, not bat an eye, not be caught dead, not born yesterday, not breathe a word, not built that way, not by a long shot, not by any means, notch, notch baby
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.