Inexact measurements can have devastating effects in sciences where precision is of paramount importance. In contrast, morphological sciences rely heavily on description, comparison, and estimation to make meaningful inferences about the structure of humans and other animals. A review of the 1918 edition of Gray's Anatomy shows that the tendency to approximate was as marked nearly a century ago as it is today. Occasionally, objects of comparison may themselves become obsolete, necessitating changes in descriptive terminology. Anat Sci Ed 2:135‐136, 2009 © 2009 American Association of Anatomists.