wackadooEnglishOxford New American Dictionarywackadoo /ˈwakəˌdo͞o, ˈwækəˌdu / (also whackadoo) US informal ▸ noun an eccentric or fanatical person: he seems like a good guy even if he is a wackadoo. ▸ adjective eccentric or fanatical: out of the blue, he would do something completely wackadoo. – ORIGIN 1950s : probably from wack2 or wacky.
EnglishOxford New American DictionaryEnglishOxford New American Dictionary
EnglishOxford New American Dictionary