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trĭ-pĕdālis, e, adj. [ter], of three feet in measure: latitudo fenestrae, Varr. R. R. 3, 9, 6: altitudo, Plin. 17, 22, 35, § 167: crassitudo parietis, id. 18, 30, 73, § 301: caulis, id. 27, 12, 79, § 104: parma, Liv. 38, 21, 13.