open one's mouth

phrase

: to speak
He says something stupid every time he opens his mouth.

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open one's mind
open one's mouth
open out
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Cite this Entry

“Open one's mouth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/open%20one%27s%20mouth. Accessed 14 Mar. 2026.

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