An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1a) A specified quantity of medicine taken at any one time.
1b) The amount of radiation administered as therapy to a given site.
2a) To give or prescribe something, such as medicine, in specified amounts.
2b) To give someone a dose of medicine to.

M.E., from M.Fr. dose, from L.L. dosis, from Gk. dosis "a portion prescribed," literally "a giving," used by Galen and other Gk. physicians to mean an amount of medicine, from stem of didonai "to give."

Doz, loan from Fr., as above. Dozidan infinitive from doz.