Trapezium or trapezoid?
The American definition is for a trapezoid to have two parallel sides, a trapezium to have none.
The British definition is the other way round.
Which are we going to use? Of course we're going to reference the fact that there are two different definitions, but one for the "main" definition?
IMO the word "trapezium" has a more symmetrical sound than "trapezoid" which sounds more clumsy and irregular, so it sounds "right" for the British definition to be used, for "trapezium" to be used for the more regular shape having two sides parallel, and "trapezoid" for that most irregular of quadrilaterals, that awkward beast that won't be fitted into any category. --prime mover (talk) 22:07, 4 March 2009 (UTC)
Hummm... I would say that a trapezoid has two parallel sides. I think our best approach to this would be to have both pages mentioning both definitions, and let the person writing a proof choose which one they would like to use. --Joe (talk) 18:42, 5 March 2009 (UTC)