The Anatomy of an Altitude
Altitudes have ear, stem, foot, and root
FYI, strangely enough, the midpoint of the ear is called not external acoustic meatus nor ear canal or ear drum but Euler point. No less strange is the fact that the point where the ear is attached to the stem is known not as a skull, or head, or neck, but the orthocenter. As Siamese triples, the three altitudes of a triangle are joined at the orthocenter but, of course, each has its own foot and other anatomical items.
- Jerzy Kocik and Andrzej Solecki, Disentangling a Triangle, Am Math Monthly 116 (March 2009), 228-237