Wacko/ˈwækəʊ/nounAn amusingly eccentric or irrational person.Synonyms: kook, odd duck, weirdoadjectiveAmusingly eccentric or irrational.Synonyms: kooky, oddballish, pixilatedinterjectionHurrah!Synonyms: get in, huzzah, woo hoo🔗 Explore synonyms & relationships🌍 See word origin & history