shut up (v.)
c. 1400, "keep from view or use, render inaccessible" early 15c., "to lock up, confine," from shut (v.) + up (adv.). The meaning "cause to stop talking" is from 1814 (Jane Austen). The intransitive meaning "cease from speaking" is from 1840, also as a command to be silent, sometimes colloquialized in print as shuddup (1940). Put up or shut up "defend yourself or be silent" is U.S. slang, by 1868.
updated on September 22, 2022