PS
the axes aren’t in quadrants. you can quote me.

on the other hand, i’m fanatical enough to believe
that “noon” and “midnight” are neither AM nor PM
(essentially because zero is neither positive nor negative).
and even that moreover this should be obvious if one knows
what the letters stand for.

so maybe you’d better find another source.

TRAPEZOID. The usual definition of a trapezoid requires that it have exactly one pair of parallel sides. However, the UCSMP textbook Geometry (1997) has the definition “a quadrilateral with at least one pair of parallel sides.” (In this textbook, an isosceles trapezoid is defined as “a trapezoid with a pair of base angles equal in measure.”) According to Chris White, the Cresent Dictionary of Mathematics by William Karush (1962) defines trapezoid as “A quadrilateral which has exactly one pair of parallel sides (sometimes, the parallelogram, with both pairs of sides parallel, is included).”

TRAPEZOID/TRAPEZIUM. In the United States, a trapezoid is generally defined as a quadrilateral with exactly one pair of parallel sides and a trapezium is a quadrilateral with no sides parallel. However, until the end of the eighteenth century, the definitions for these two terms were reversed, and outside the United States even today the definitions are often reversed.