(Chapter 29) Footnote 21:

See Introductio seu medicus 14.724.2 and 756.5-7 (by Pseudo-Galen, a post-Galenic writer). Vesalius cites Hippocrates De articulis in the margin; see 46.7, 47.5, etc. The word is found as early as Homer, Il. 5.305.