| 释义 |
tacnode Geom.|ˈtæknəʊd|
[f. L. tac-tus touch + node.]
A point at which two parts of the same curve have ordinary contact.
1852Cayley Math. Papers (1889) II. 28 The tacnode is a double point where two branches touch. 1873Salmon Higher Plane Curves 207 Two nodes may coincide, giving rise to the singularity called a tacnode; this is in fact an ordinary (two-pointed) contact of two branches of the curve.
b. attrib. ˈtacnode-ˈcusp, the singularity of a curve which arises when a cusp and an immediately following tangency of the two branches coalesce.
1873Salmon Higher Plane Curves (1879) 207. |