English

Noun

double point ‎(plural double points)

1. A symbol, such as a colon, composed of two points.
   • Henry Bradshaw

     As with the printers a full-point, a double point or colon, and a triple point, are each of them single types, the matter was still more simplified.

2. (mathematics) A point on a curve at which there are two tangents (because it touches itself, or has a cusp)