dose (n.) Look up dose at Dictionary.com
c.1600, from Middle French dose (15c.), from Late Latin dosis, from Greek dosis "a portion prescribed," literally "a giving," used by Galen and other Greek physicians to mean an amount of medicine, from stem of didonai "to give" (see date (n.1)). Slang meaning "venereal disease" is from 1914.
dose (v.) Look up dose at Dictionary.com
1650s, from dose (n.). Related: Dosed; dosing.