off-the-wall

See also: off the wall

English edit

Perhaps from baseball or other games played with a ball, alluding to unpredictable bounces.

off-the-wall (comparative more off-the-wall, superlative most off-the-wall)

(idiomatic) Wildly unconventional; bizarre; absurd.
What kind of a harebrained, off-the-wall idea is that?

She is a very off-the-wall character.
- 2015 March 19, Alessandra Stanley, “'Empire' Finale Review: A Sizzling End to Season One”, in New York Times‎^[1]:
  What makes it surprising, though, are the glimmers of wit and self-awareness beneath all the rap star swagger and over-the-top confrontations. Even the fervid finale had a few off-the-wall side jokes.
(idiomatic) Of a person's behaviour: greatly inappropriate.
- 2012, Reginald Pierce, The Paladin, page 204:
  All of their friends were amazed that they were familiar with a war hero. Some began to understand Chips' moods and drinking. His "off the wall" behaviour at times. And unknowingly they were "forgiving" him.

wildly unconventional; bizarre; absurd

greatly inappropriate