Definition of wacko
Origin and Etymology of wacko
First Known Use: 1975
Examples of wacko in a sentence
She's nice but her sister's a real wacko.
<some wacko has been sending the actress increasingly disturbing letters>
First Known Use of wacko
WACKO Defined for English Language Learners
Definition of wacko for English Language Learners
: a person who is crazy or very strange and unusual
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Thesaurus: All synonyms and antonyms for wacko
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