keep one's own counsel
Say little or nothing about one's opinions or intentions. For example, Betty is notorious for keeping her own counsel; you never know what she really thinks. This expression employs counsel in the sense of “a secret,” a usage dating from about 1300.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
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