crack up crack-the-whip • crack-up · · · Info · Definitions · Synonyms · Characters · · crack up · · Text Common · · Latin · · Scripts 8 · · Length 2 · · Syllables Definitions · · · (noun) a mental or physical breakdown. Synonyms: breakdown, crack-up. · · Noun Definition 1 (verb) suffer a nervous breakdown. Synonyms: crack up, crack, crock up, break up, collapse. · · Verb Definition 1 (verb) rhapsodize about. Synonyms: crack up. · · Verb Definition 2 (verb) laugh unrestrainedly. Synonyms: break up, crack up. · · Verb Definition 3 Synonyms · · · breakdown · · Synonym 1 crack-up · · Synonym 2 crack · · Synonym 3 crock up · · Synonym 4 break up · · Synonym 5 collapse · · Synonym 6 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 k latin small letter k U+006B p latin small letter p U+0070 r latin small letter r U+0072 u latin small letter u U+0075