- From the image of a solid rectangle 'slipping down' into a pear shape, thus 'the bottom drops out'.
- Presumably from the image of a balloon or football losing its spherical shape after puncturing.
go pear-shaped (third-person singular simple present goes pear-shaped, present participle going pear-shaped, simple past went pear-shaped, past participle gone pear-shaped)
- (Britain, New Zealand, idiomatic) To go wrong; to go awry. [from 1990s]
2002, Mike Skinner (lyrics), “Stay Positive”, in Original Pirate Material, performed by The Streets:
I hope you understand me / I ain't no preaching fucker and I ain't no do-goody-goody either / This is about when shit goes pear-shaped
2017, Eric A Meyer; Estelle Weyl, CSS: The Definitive Guide: Visual Presentation for the Web, Kindle edition, O'Reilly Media, page 697:
There are a few cases that need to be covered, as they fall under the general umbrella of “what grids do when things go pear-shaped.”
- ^ Jonathon Green (2005) Cassell's Dictionary of Slang, second edition, London: Weidenfeld & Nicolson
Tony Thorne (2005) Dictionary of Contemporary Slang, third edition, London: A & C Black