Trapezium, plural trapezia, may refer to:

• Trapezium, in British and other forms of English, a trapezoid, a quadrilateral that has exactly one pair of parallel sides
• Trapezium, in North American English, an irregular quadrilateral with no sides parallel
• Trapezium (bivalve), a genus of molluscs in the family Trapezidae
• Trapezium (bone), a bone in the hand
• Trapezia (crab), a genus of crabs
• Trapezium (novel), a Japanese novel by Kazumi Takayama

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