n.pl. tra·pe·zi·ums or tra·pe·zi·a(-ze-ə)
a. A quadrilateral having no parallel sides.
b. Chiefly British A trapezoid.
2. Anatomy A bone in the wrist at the base of the thumb.
[Originally, a quadrilateral with two parallel sides (later confused withTRAPEZOID, originally, a quadrilateral having no parallel sides), fromModern Latintrapezium, a quadrilateral with two parallel sides, fromLate Greektrapezion, fromGreek, diminutive oftrapeza, table : tra-, four; see kwetwer- in the Appendix of Indo-European roots + peza, foot; see ped- in the Appendix of Indo-European roots.]
(click for a larger image)trapezium
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