crack up

== English == === Etymology === Compare Japanese 笑う (warau, “laugh, smile”), suffixed from Japanese 割る (waru, “crack”). === Pronunciation === IPA(key): /ˈkɹæk ˈʌp/ === Verb === crack up (third-person singular simple present cracks up, present participle cracking up, simple past and past participle cracked up) To laugh. (idiomatic, intransitive) To laugh heartily. (idiomatic, transitive) To cause to laugh heartily. (slang, intransitive) To tease (someone) or tell jokes at the expense of (someone). He's always cracking up at me about that. To break. (idiomatic, intransitive, dated in US) To become insane; to suffer a mental breakdown. (idiomatic) To break down or fall apart; to stop functioning; to shatter. The university was really cracking up, losing faculty, students and donors, and it seemed like to go under. My motorcycle cracked up before I arrived. (idiomatic, transitive) To separate a group. I have to crack up that little clique. (US) To crash an aircraft or automobile. (transitive) To remove the shell from nuts. We can send you a hundred pounds a month of pecans to crack up. (transitive) To crack (petroleum). (to break down (a complex molecule), especially with the application of heat: to pyrolyse) The refinery cracks up the heavier oils. To affect the image of something. (slang, transitive) To praise or applaud (something); to promote a positive view of (something). She wasn't as impressive as Katie cracked her up. (dated, transitive) To insult, demean or harm the image of (something). Those who have been cracking up the agricultural industry will hopefully reconsider their denigration of it. (transitive, informal, usually passive voice, chiefly in the negative) To cry up; to extol. (slang, intransitive) To smoke crack cocaine. ==== Derived terms ==== all it's cracked up to be ==== Translations ==== === Adjective === crack up (comparative more crack up, superlative most crack up) (New Zealand, colloquial) Funny; hilarious === References === === Further reading === “crack up”, in OneLook Dictionary Search. William Dwight Whitney, Benjamin Eli Smith, editors (1895–1910), “crack”, in The Century Dictionary […], New York, N.Y.: The Century Co., →OCLC.