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Synonyms

clam up

British  

verb

  1. informal (intr, adverb) to keep or become silent or withhold information

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

clam up Idioms  
  1. Refuse to talk or respond, as in Whenever she asks her teenager about his activities, he clams up. This term alludes to the tightly closed valves of a live clam. [Slang; early 1900s]


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

However, he clammed up when Welker asked him to share other methods in which he might stay on.

From Salon

Another factor is “just having extreme social anxiety for a long, long time. People were fascinating to me, but also scary. I would kind of clam up around people because my brain would short-circuit.”

From Los Angeles Times

“What kind of helpful information would be in books about a wannabe Chosen One who clams up when it’s time to stop the bad guy?”

From Literature

“But as soon as we turned our microphones on and stuck them in their faces, they totally clammed up.”

From New York Times

“There was a dreadful silence, and they literally clammed up. It was incredibly unnerving for the White House and the Pentagon.”

From Washington Times