adjective
wacko
WA-koh
adjective
1
Eccentric or irrational in a way that's amusing rather than alarming.
"His wacko theories about the moon landing kept us laughing all night."
noun
1
A person who behaves in an eccentric or irrational way.
"The neighbours think he's a wacko for talking to his plants."
How to Use Wacko
Learner’s notesIn plain EnglishA playful word for someone or something a bit crazy or over-the-top.
When to use it
Informal and can be mildly mocking; use with care about people, not just ideas.
Common pairings
a total wacko
wacko idea
Word Forms
more wacko comparative, wackos plural, wackoes plural, most wacko superlative
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His _____ theories about the moon landing kept us laughing all night.
Etymology
Formed from "wack(y)" plus the informal "-o" ending, the same pattern seen in words like "cheapo" or "weirdo".