Clam up
Clam up verb - To stop talking.
Dam up
Dam up verb - Obstruct with, or as if with, a dam.
Cite this Source
Dam up and Clam up. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/clam_up/dam_up
Clam up & Dam up. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/clam_up/dam_up>.
Dam up or Clam up. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/clam_up/dam_up.
Google Ngram Viewer shows how "clam up" and "dam up" have occurred on timeline