Ageometresia or ageometria is a word describing a defect in a work of geometry.
An early usage of the word was in writings of François Viète on Copernicus. As another instance, Johannes Kepler, having no direct and geometrical method of finding certain matters in his elliptical theory, namely how to calculate the true anomaly from the mean anomaly, has been charged by others with ageometresia.
Although Viète wrote in Latin, the word “ageometresia” is Greek, and the same Greek word has also subsequently been used by writers in English. As well as its usage to indicate faults in the works of professional mathematicians, “ageometria” has also been used to describe a form of dyscalculia, a disability that prevents students from understanding geometry.