[n. of action, f. L. circumvolvĕre, circumvolūt- to roll round. Cf. F. circonvolution 16th c. in Littré.]
1. Rolling, whirling, or turning round an axis or center; revolution, rotation, gyration.
1447. Bokenham, Seyntys (1835), 144. Whan Phebus … Descendyd was…. To þe lowest part by circumuolucyoun Of þe Zodyac.
1610. Healey, St. Aug. Citie of God, XVIII. viii. To behold the circumvolution of the starres.
1615. G. Sandys, Trav., IV. 307. Circe signifieth no other then the Suns circumuolution.
1635. N. Carpenter, Geog. Del., I. ii. 33. One Beame of the circle, by whose circumuolution is produced the circumference of it.
1751. Johnson, Rambler, No. 102, ¶ 12. Within the eddy … where the circumvolution was weak.
1849. Mrs. Somerville, Connect. Phys. Sc., § 34. 371. The magnet tends to follow the circumvolution of the plate.
b. (with pl.) A single complete turn, revolution or rotation.
1570. Billingsley, Euclid, XI. 16. 317. A Cone is a regular body produced of one circumuolution of a rectangle triangle.
1641. Wilkins, Math. Magick, II. xv. (1648), 289. Every circumvolution voiding onely so much as is contained in one Helix?
1712. Pope, Spect., No. 408, ¶ 1. It is of more Consequence to adjust the true Nature and Measures of Right and Wrong, than to settle the Distance of the Planets, and compute the Times of their Circumvolutions.
1853. G. Johnston, Nat. Hist. E. Bord., 101. The number of circumvolutions is the true index to the time of day!
c. Of time, and fig.
1610. Healey, St. Aug. Citie of God, xxi. 17. 858. That rotation and circumvolution of misery and blisse.
1863. Heroes, Philos. & Courtiers Louis XVI., II. 57. During awful circumvolutions of endless Time.
2. The winding, rolling or folding of a thing round something else. b. A single fold or turn of anything so wound.
1599. A. M., trans. Gabelhouer’s Bk. Physicke, 21/2. I … take my beginning of circumvolutione at the knees.
1634. T. Johnson, Parey’s Chirurg., XIV. iv. (1678), 325. Binding … performed with many circumvolutions or wrappings about.
1713. Derham, Phys. Theol., X. i. 458. These Claspers taking hold of anything … at Hand … by a natural Circumvolution.
1856. Ferrier, Inst. Metaph., Introd. § 51. Like a gigantic boa-constrictor … He may be breaking every bone in their body in his stringent circumvolutions.
3. A winding, or moving in a sinuous course; concr. a winding, a sinuosity. Also fig.
1633. T. Adams, Exp. 2 Pet. ii. (1865), 502/1. He that hath strayed into these thickets, will be so mazed with intricate circumvolutions, that [etc.].
1742. H. Baker, Microsc., II. xii. 143. The circular Wrinkles or Circumvolutions encompassing the [muscular] Fibres.
1750. Johnson, Rambler, No. 65, ¶ 3. A gentle river that … watered a large region with innumerable circumvolutions.
1844. Disraeli, Coningsby, VI. ii. 230. Neither time nor temper for sentimental circumvolutions.
1868. Duncan, Insect World, Introd. 9. A lengthened tubular organ … forming more or less numerous circumvolutions.
† b. Anat. (pl.) The convolutions of the surface of the brain. Obs.
1578. Banister, Hist. Man, VIII. 100. The circumuolutions and turninges in the brayne.
1713. Cheselden, Anat., III. xiv. (1726), 242. Between the two hemispheres of the Cerebrum, lower than the circumvolutions.
c. Arch. (pl.)
1876. Gwilt, Archit., Gloss., Circumvolutions, the turns in the spiral of the Ionic capital, which are usually three, but there are four in the capitals of the temple of Minerva Polias.
