lips are sealed, his/my

(one's) lips are sealed

One will not tell anyone; one will keep this a secret. Most often used in the expression "my lips are sealed." A: "Please don't tell anyone about this, I'm so embarrassed." B: "My lips are sealed." I told him not to say anything, and he said his lips are sealed, so hopefully he'll be able to keep a secret this time.
See also: lip, seal

my lips are sealed

I will not tell anyone; I will keep this a secret. A: "Please don't tell anyone about this, I'm so embarrassed." B: "My lips are sealed."
See also: lip, seal
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

My lips are sealed.

Fig. I will tell no one this secret or this gossip. Mary: I hope you don't tell anyone about this. Alice: Don't worry. My lips are sealed. Bob: Don't you dare tell her I told you. Bill: My lips are sealed.
See also: lip, seal
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

my lips are ˈsealed

(informal, humorous) I promise not to tell your secret: Don’t worry, I won’t tell anybody. My lips are sealed.
See also: lip, seal
Farlex Partner Idioms Dictionary © Farlex 2017

(one's) lips are sealed

Used to indicate that one will not disclose a piece of information.
See also: lip, seal
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

lips are sealed, his/my

He/I will keep this secret. Although the idea of keeping one’s mouth tightly shut is much older and sealing up someone else’s lips dates from the late 1700s, this particular expression became current only in the early twentieth century. It was much repeated by Prime Minister Stanley Baldwin when asked about the rumored abdication of King Edward VIII, who wished to (and eventually did) marry a divorced American, Wallis Simpson. See also mum's the word.
See also: lip
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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