a. [f. mod.L. TRAPEZIUM + -AL.]
1. Of or pertaining to a trapezium; having the form of a trapezium, trapeziform.
1681. trans. Willis’ Rem. Med. Wks., Vocab., Trapezial, belonging to a geometrical figure, so called of four sides.
1703. T. N., City & C. Purchaser, 249. At each corner of the Newel there is a trapezial Hall-pace.
1852. Dana, Crust., I. 312. Their trapezial or quadrate form.
2. Anat. Pertaining to the trapezium (in either sense), or to the trapezius muscle.
1891. Cent. Dict., Trapezial, in anat., pertaining to the trapezius: as, trapezial fibers or action.
1899. Syd. Soc. Lex., Trapezial, pertaining to the Trapezium or Trapezius.
