(found at http://www.ucle.org/ucle9.html)
This expression is interesting because "pear-shaped" has been long acknowledged as a description
for an elegant cut of diamond. This pedigree would appear to give "pear-shaped" a positive
description. "Pear-shaped" can also be used to describe the voluptuous anatomies portrayed by
classical artists such as Poussin, Rubens, Raphael, or Rossetti.
"It went pear-shaped" is used in modern English to signify a comedic fiasco or similar disaster. In
almost every circumstance, it refers to an undertaking or project that resulted in failure, but caused
no grievous harm to anyone involved. Further, it provides a gentle suggestion that the fiasco was a
result of nature and beyond the control of any specific individual. It is not regarded as vulgar or
Despite its common usage, the origin of the phrase remains obscure. Some sources attest that its
origins lie in ballooning, and that a pear suggests the shape of a collapsed balloon. I can't find
support for this etymology at http://www.ballooning.org/ballooning/glossary.html.
Others suggest that "pear-shaped" is rooted in aircraft terminology. The story goes that certain
types of aircraft engine casings might go "pear-shaped" in the event of failure. Unfortunately, there is
no convincing citation to accompany this claim.
Maths experts and "Quants" can be expected to attest that "pear-shaped" refers to a so-called
"normal" or "Gaussian" distribution where the extremities of the distribution have become enlarged.
In such a situation, improbable events would become much more probable. This is, at the moment,
the preferred origin for "It's all gone pear-shaped".
Editor's note: If you have a definitive citation for "pear-shaped", please send email to