wacky

Etymology 1

From whack, meaning someone who whacked his head onto something often, hence being weird.

adj

1. Zany; eccentric.
   Though the idea of placing wacky made-up characters in a real-life context was carried over from Da Ali G Show—wherein Buzz Aldrin was once asked if he was upset that Michael Jackson got all the credit for inventing the moonwalk—Sacha Baron Cohen’s Borat felt like something new, an attempt to square an improvised, guerrilla style of underground comedy with reality-TV stunt shows like Jackass or Fear Factor. May 15, 2012, Scott Tobias, “Film: Reviews: The Dictator”, in The Onion AV Club
   How do artists and curators come up with titles for exhibitions? They seem to get wackier all the time. 2013-09-25, Jonathan Jones, “Dissecting the Exploding Whale: why do modern art shows have odd names?”, in The Guardian

Etymology 2

noun

1. Alternative form of wacke