sinusoidn.
/ˈsʌɪnəsɔɪd/, U.S. /ˈsaɪnəˌsɔɪd/ 1. Mathematics. A curve of sines (curve n. 2).
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the world > relative properties > number > geometry > curve > [noun] > other
quadratrix1656
section1665
family1705
semiparabola1728
tractrix1728
witcha1760
tractory1820
sinusoid1823
tractatrix1828
indicatrix1841
hodograph1847
tetrazomal1867
space curve1875
horograph1879
hypercycle1889
Peano curve1900
multiple arc1967
unknot1971
fractal1975
analemma1978
1823 D. Lardner Syst. Algebraic Geom. I. 200 A curve, represented by the equation y = sin. x, related to rectangular co-ordinates, is called the curve of sines, or the sinusoid.
1876 Proc. London Math. Soc. 7 213 Prof. Cayley described a surface, depending upon the sinusoid, which was being constructed for him.
1884 tr. Glaser de Cew's Magn. & Dynamo-electric Machines 254 If the magnetic field in which the armature rotated were uniform, this curve would be a true ‘sinusoid’, or curve of sines.
2. A blood vessel similar in size to a capillary but irregular in shape and without the continuous endothelial lining of capillaries.
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the world > life > the body > vascular system > blood vessel > sinusoid > [noun]
sinusoid1900
1900 Minot in Proc. Boston Nat. Hist. Soc. 185 The [blood-] vessels of the first type are true capillaries... The vessels of the second type I propose to name ‘sinusoids’, on account of their resemblance to true sinus and also to separate them clearly from genuine capillaries.
1920 Nature 27 May 411/1 A system of wide sinusoids (renal venous meshwork), which has no connection with the intertubular plexus.
1974 D. Webster & M. Webster Compar. Vertebr. Morphol. xiii. 315 In the mammalian adrenal cortex the steroidogenic tissues can be divided into zones on the basis of the arrangement of cells and their relationships to the numerous blood sinusoids.
This entry has not yet been fully updated (first published 1911; most recently modified version published online March 2022).
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n.1823