Crack up
Crack up verb - To declare enthusiastic approval of.
Knock dead and crack up are semantically related In some cases you can use "Knock dead" instead a verb "Crack up".
Knock dead
Crack up and knock dead are semantically related in entertain topic. Sometimes you can use "Crack up" instead a verb phrase "Knock dead", if it concerns topics such as amuse.
Cite this Source
Knock dead and Crack up. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/crack_up/knock_dead
Crack up & Knock dead. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/crack_up/knock_dead>.
Knock dead or Crack up. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/crack_up/knock_dead.
Google Ngram Viewer shows how "crack up" and "knock dead" have occurred on timeline