trapezoid (n.) Look up trapezoid at
1706, "a trapezium," from Modern Latin trapezoides, from Late Greek trapezoeides, noun use by Euclid of Greek trapezoeides "trapezium-shaped," from trapeza, literally "table" (see trapezium), + -oeides "shaped" (see -oid). Technically, a plane four-sided figure with no two sides parallel. But in English since c.1800, often confused with trapezium in its sense of "a quadrilateral figure having only sides parallel and two not."