a. [ad. mod.L. zōnālis, f. L. zōna ZONE.]
1. Characterized by or arranged in zones, circles, or rings; of the nature of or forming a zone.
1873. A. Wilson, Elem. Zool., I. ii. 22. In ‘zonal’ symmetry the merosomes are arranged in zones, one after another, in a longitudinal axis.
1888. Rutley, Rock-Forming Min., 124. The small spherical crystalline aggregates show … a concentric zonal structure.
b. Marked with zones or circular bands of color: applied to varieties of pelargonium or geranium having the leaves so marked.
1868. Morn. Star, 17 June. The cultivators of zonal pelargoniums, or variegated leaf-coloured geraniums, had a grand competition.
1908. Nation, 22 Feb., 756/2. They [professional florists] have seen the zonal geranium reigning as a queen while the daffodil grew unnoticed in cottage gardens.
2. Math. & Cryst. Relating to a zone or zones of a sphere, or of a crystalline form: see ZONE sb. 8.
1867. Thomson & Tait, Nat. Phil., § 781. These circles … are … all in parallel planes … and cut the spherical surface into zones, in which case the harmonic is called zonal.
3. Pertaining or relating to, involving, or constituting a ‘zone’ or ‘zones,’ i.e., regions or areas distinctively characterized in some way: see ZONE sb. 2 b, 7.
1881. Knowledge, 7 July, 92. The six zonal areas we have thus described will serve our purpose admirably for grouping together our Seaside Health-Resorts.
1890. Nature, 4 Sept., 454/2. Zonal divisions are based upon these bogus species and conclusions drawn from them.
1893. Geikie, Text-bk. Geol., VI. III. i. (ed. 3), 876. In tracing the zonal parallelism of the Triassic succession within the Alps themselves.
1904. Edin. Rev., Jan., 219. The study and correlation of strata characterised by the dominance of a zone-fossil forms zonal geology.
1909. R. W. Mason, in Spectator, 29 May, 856/2. The companies adopted a zonal tariff (as the State has done for telephone purposes) because the expense of transmitting a telegram is largely proportioned by the distance it is transmitted.
Hence Zonality, zonal character or distribution; Zonally adv., in or according to zones.
1873. A. Wilson, Elem. Zool., I. ii. 22. The segments … of the body, which are arranged zonally along a longitudinal axis.
1889. Amer. Nat., XXIII. 814. Crystals of the hyacinth variety of quartz … contain numerous inclusions of anhydrite arranged zonally.
1909. Daily Chron., 21 March, 3/5. The zonality of the flowers.
