a. [f. TESSERA + -AL.]
1. Of, pertaining to, or resembling a tessera or tesseræ; composed of tessera.
1846. Worcester cites Edinb. Rev.
2. Cryst. = ISOMETRIC 3, CUBIC a. 1 c.
1854. Pereiras Pol. Light, 191. The cubic or octohedral system. Synonymes.The regular, the tessular, the tesseral, or the isometric system.
1878. Gurney, Crystallogr., 37. Crystals possessing this highest possible degree of symmetry are said to belong to the Cubic or Tesseral System.
3. Math. Relating to the tesseræ of a spherical surface (see TESSERA 2 b), as in tesseral harmonic, a spherical surface harmonic which is the product of two factors depending respectively on latitude and longitude.
1873. Maxwell, Electr. & Magn. (1881), I. 196. We may now write the expressions for the two tesseral harmonics. Ibid., 198. To find the surface integral of the square of any tesseral harmonic taken over the sphere.
1887. Hobson, in Trans. Camb. Philos. Soc. (1889), XIV. 211. The zonal and tesseral harmonics are exhibited as series.