One of the mysteries of the English language finally explained.
An imaginary ellipsoidal surface whose axes represent the refractive indices of a crystal for light following different directions with respect to the crystal axes.
- ‘Other contributions to differential geometry which occur in this work include his invention of the ‘Dupin indicatrix’ which gives an indication of the local behaviour of a surface up to the terms of degree two.’
Late 19th century: modern Latin, feminine of Latin indicator ‘something that points out’.
In this article we explore how to impress employers with a spot-on CV.