noun, plural wack·os.
Examples from the Web for wacko
At first this plays like some sort of bizarre SNL sketch: the wacko physician.Why Is Louis C.K. So Funny? He Uses Humor as a Moral Compass.|Andrew Romano|May 2, 2014|DAILY BEAST
McCain called Cruz a “wacko bird” and later took it back, about as insincerely as possible.
The hysteria and hostage taking of Wacko Bird Inc. is not reasonably matched to the current situation.
The GOP “suicide caucus”, led by proud “wacko bird” Sen. Ted Cruz, was, not surprisingly, spawned from a faulty premise.
In a country where six of 10 voters already think the government is too big, the wacko bird caucus has got a lot of room to fly.Ted Cruz Might Just Have Won the Future for the GOP|Nick Gillespie|September 25, 2013|DAILY BEAST
British Dictionary definitions for wacko
noun plural wackos
Word Origin for wacko
Word Origin and History for wacko
extended form of wack, recorded from 1977.