Clam up is a idiom that came into use in the twentieth century. We will examine the meaning of the idiom clam up, where it came from and some examples of its use in sentences.
To clam up means to go silent, to be quiet, to shut up, to refuse to speak. The idiom clam up is often used to describe the silence of a witness who is being interrogated. Clam up is an American idiom that was first seen in the 1910s, and references a bivalve or clam that shuts itself tight when confronted with a predator. It is very difficult to pry open a clam. The word clam is derived from the Germanic root, klam, which means squeezed together. Related phrases are clams up, clammed up, clamming up.
I suspect that if they clam up afterward and don’t ask anything else, it’s because they’re sensing your strong emotions, no matter how cheerfully you try to answer. (Outside Magazine)
Attaran, the law professor, agrees with Cotler and thinks ex-politicians like Chretien and McCallum should clam up while the matter is before the court. (Global News)
The 41-year-old Portage Township man said he intended to speak to the loss prevention officer on the way out of the store but then clammed up when it was pointed out he passed by the officer, who wound up chasing after him, police said. (The NWI Times)
Even Governor Hogan, who three months ago raised pointed questions about Mr. Loh’s role in the McNair tragedy, has clammed up. (The Baltimore Sun)