acnode

/ ˈækˌnəʊd /

noun

1. a point whose coordinates satisfy the equation of a curve although it does not lie on the curve; an isolated point. The origin is an acnode of the curve y ² + x ² = x ³

Derived Forms

• acˈnodal, adjective

Word History and Origins

Origin of acnode¹

C19: from Latin acus a needle + node

Example Sentences

Secondly, if two of the intersections coincide, say if the line infinity meets the curve in a onefold point and a twofold point, both of them real, then there is always one asymptote: the line infinity may at the twofold point touch the curve, and we have the parabolic hyperbolas; or the twofold point may be a singular point,—viz., a crunode giving the hyperbolisms of the hyperbola; an acnode, giving the hyperbolisms of the ellipse; or a cusp, giving the hyperbolisms of the parabola.

From Project Gutenberg

The singular kinds arise as before; in the crunodal and the cuspidal kinds the whole curve is an odd circuit, but in an acnodal kind the acnode must be regarded as an even circuit.

From Project Gutenberg