From Longman Dictionary of Contemporary Englishscrewballscrew‧ball /ˈskruːbɔːl $ -bɒːl/ noun [countable] especially American English informal STRANGECRAZYsomeone who seems very strange or crazy
Examples from the Corpus
screwball• They want to make screwball romantic comedies but they wind up producing sitcoms that look lost without a laugh track.• A straight-laced Wall Street banker gets mixed up in one ludicrous misunderstanding after another in George Gallo's screwball comedy. 