a. [f. Gr.-L. symmetros (Vitruvius), Gr. σύμμετρος commensurate, proportionable, symmetrical (f. σύν SYM- + μέτρον measure) + -AL.]
† 1. Agreeing in measurement, proportionable, commensurate. Obs. rare–1.
1660. H. More, Myst. Godl., V. xvi. 185. The Temple and Altar of God that are Symmetral or commensurable to the Angels measure [Rev. xi. 1].
† 2. fig. Commensurate with the Divine idea or pattern; agreeing with the Word of God (cf. quot. 1680 s.v. ASYMMETRAL, and 1683 below): applied to the early church, or its times, etc. Obs.
1660. H. More, Myst. Godl., V. xvii. § 3. 204. It was both the Doctrine of the Apostles, and Practice of the Church, while it was Symmetral, to obey the Magistrate. Ibid. (1664), Myst. Iniq., 472. The Church was Symmetral for about four hundred years after Christ. Ibid. (1681), Expos. Dan., App. ii. 270. The end of the Symmetral Ages of the Church and the beginning of the Asymmetral or of the Apostasy.
1683. G. Hickes, Case Inf. Bapt., 82. The purity of the Apostolical Ages, when the Church was represented as Symmetral by the Spirit of God, under the Symbol of Measuring the Temple of God and the Altar.
1685. H. More, Reflect. on Baxter, 29. An Authentick Church, reformed to the Pattern of the Symmetral or Primitive Ages.
3. Math. † a. Arith. and Alg. Having a common measure, commensurable. Obs.
1674. Jeake, Arith. (1696), 295. Commensurable, called also Symmetral, is when the given Numbers have a Common Divisor. Ibid. Symmetral Surdes.
b. Geom. Related to or determining symmetry; about which a figure is symmetrical: as in symmetral axis, plane = axis or plane of symmetry.
1878. Gurney, Crystallogr., 27. The two halves on either side of this symmetral plane are in all respects similar. Ibid., 37. An axis of symmetry or a symmetral axis.
