Definition of evolute in English:
evolute
(also evolute curve)
noun ˈɛvəl(j)uːtˈiːvəl(j)uːtˈɛvəˌlut
Mathematics A curve which is the locus of the centres of curvature of another curve (its involute).
〔数〕渐屈线，法包线
Example sentencesExamples
- Hence a curve has a unique evolute but infinitely many involutes.
- On 22 January 1769 Monge wrote to Bossut explaining that he was writing a work on the evolutes of curves of double curvature.
- He gives propositions determining the centre of curvature which lead immediately to the Cartesian equation of the evolute.
- He defines evolutes and involutes of curves and, after giving some elementary properties, finds the evolutes of the cycloid and of the parabola.
- Of course the evolute of an involute of a circle is a circle.
adjective ˈɛvəl(j)uːtˈiːvəl(j)uːt
Zoology Botany Rolled outwards at the edges.
〔动，植〕展开的，外卷的
外卷的壳。
Example sentencesExamples
- The second lineage contained A. nitida, which became more involute and axially compressed on the umbilical side, and its first descendant, A. mckannai, which developed evolute coiling and a moderately wide umbilicus.
- The general shell characters are the evolute coiling and the median keel that is always higher than the lateral ones.
- It essentially separates early (higher scores) and later (lower scores) representatives of the species, which tended to develop evolute coiling through geologic time.
- These younger descendants differ from Goniatites in their evolute inner whorls, their wider external lobe, and their higher median saddle.
- Most clymeniids and contemporary goniatitids (with both evolute and involute shells) declined before the last anoxic episode, known as the Hangenberg event, which was followed by a major regression.
Origin
Mid 18th century: from Latin evolutus, past participle of evolvere 'roll out' (see evolve).