wack·y (wăk'ē) also whack·y (hwăk'ē, wăk'ē)
adj. Slang, -i·er, also -i·er, -i·est, also -i·est.

1. Eccentric or irrational: a wacky person.
2. Crazy; silly: a wacky outfit.

[Variant of whacky, probably from the phrase out of whack. See whack.]

wackily wack'i·ly adv.
wackiness wack'i·ness n.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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