Medicine, or medical science, is the science and practice of treating damage and ailments that affect the mind or body of a humanoid. It also deals in the prevention and diagnosis of said damage and ailments.
In the late 20th century, the fad known as cryonics froze people at the time of death with the hope that some time in the future, when presumably medical science had a cure for whatever killed them, they would be thawed back to life, healed and sent on about their business. (TNG: "The Neutral Zone")
In the 24th century, the Federation had a policy of not restricting access to its medical supplies. William Riker informed Governor Vagh of this policy when informed that Kriosian rebels had been found to be in possession of Federation medical supplies in 2367. (TNG: "The Mind's Eye")