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English definition of “wacko”

wacko

noun [C]     /ˈwæk.əʊ/ US  /-oʊ/ (plural wackos) mainly US informal
a person whose behaviour is strange and different from that of most peopleStrange, suspicious and unnatural things and people
(Definition of wacko noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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