spheroidal, a.
(sfɛˈrɔɪdəl)
Also sphæroidal.
[f. spheroid n. + -al1. So F. sphéroïdal, Sp. and Pg. esferoidal.]
1. a. Of form, figure, etc.: Characteristic of a spheroid; approximately spherical.
| 1781 Phil. Trans. LXXI. 503 Allowing for the spheroidal figure of the earth. 1802 Playfair Illustr. Huttonian The. 493 To account for its assuming the spheroidal figure. 1845 Todd & Bowman Phys. Anat. I. 138 The spheroidal form of the cranium. 1890 Science-Gossip XXVI. 49/1 While the heavier portions..were being drawn together so as to acquire a spheroidal contour. |
b. spheroidal condition or
spheroidal state: (see
quots. 1860 and 1871).
| 1855 Scoffern in Orr's Circ. Sci., Elem. Chem. 190 If it be projected upon a capsule of platinum, maintained at a red heat, the salt..will assume the spheroidal condition. 1860 Ure's Dict. Arts (ed. 5) III. 732 Spheroidal state, the name given by Boutigny to the condition assumed by water when projected into red hot vessels. 1871 B. Stewart Heat (ed. 2) §110 Vaporization in the Spheroidal Condition, where a liquid evaporates slowly although in apparent contact with a very hot substance. |
2. a. Having the form of a spheroid.
| 1798 Hutton Course Math. (1807) II. 348 The spheroidal hollow in the bottom of the bore. 1822 J. Parkinson Outlines Oryctol. 77 A stony polypifer, fixed, in a simple hemi⁓sphærical or sphæroidal mass. 1867 J. Hogg Microsc. ii. i. 271 A splitting up..into six or eight masses, which become spheroidal sporules. 1878 Newcomb Pop. Astron. iv. iii. 998 A constant flattening of the spheroidal atmosphere. |
| Comb. 1891 Moullin Surg. 138 Spheroidal-celled Cancer..occurs in the breast,..nose, and palate. |
b. In special applications (see
quots.).
| 1805–17 R. Jameson Char. Min. (ed. 3) 209 Spheroidal, when its surface consists of forty-eight convex faces, as in the diamond. 1842 Gwilt Archit. Gloss., Spheroidal Bracketing, that formed to receive the plastering of a spheroid. 1881 Mivart Cat 26 Or they may be rounded, forming spheroidal epithelium. 1897 Allbutt's Syst. Med. III. 977 Spheroidal carcinoma is rare in the large intestine. |
c. Metallurgy.
= nodular a. 4.
| 1920 Jrnl. Iron & Steel Inst. CII. 261 The present experiments were undertaken to clear up the cause of the formation of the spheroidal cementite. 1957 Technology July 172/3 To-day, nodular or spheroidal graphite cast iron is an article of commerical manufacture. 1977 Metals Abstr. X. 1801/1 Tests were made on boronizing spheroidal graphite cast iron (SGCI) to improve surface hardness and wear resistance. |
3. Dealing with the properties of spheroids.
| 1876–7 Cayley Math. Papers (1896) IX. 197 The fundamental formulæ of Spheroidal Trigonometry are those which belong to a right-angled triangle. |
Hence
spheˈroidally adv., after a spheroidal manner; so as to form spheroids.
| 1888 Q. Jrnl. Geol. Soc. XLIV. 450 The great mass of Mynydd-y-Rhiw..is largely built up of spheroidally jointed rock. |