plead the Fifth

verb2

(US) To invoke the Fifth Amendment to the United States Constitution, which protects witnesses from being forced to incriminate themselves.
•
(informal, humorous) To refuse to answer a question, or refuse to speak especially when the response would be embarrassing or uncomfortable.
- Yo ain't no city in the world like this // An' if you ask how I know, I gots ta plead the fifth (1998, Miami (Will Smith song))

forms

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