mid-14c., paciente, "capable of enduring misfortune, suffering, etc., without complaint," from Old French pacient and directly from Latin patientem "bearing, supporting, suffering, enduring, permitting" (see patience). From late 14c. as "slow to anger, self-restrained, having the temper which endures trials and provocations." From late 15c. as "awaiting or expecting an outcome calmly and without discontent." The meaning "pertaining to a medical patient" is late 14c., from the noun. Related: Patiently.
"suffering, injured, or sick person under medical treatment," late 14c., from Old French pacient (n.), from the adjective, from Latin patientem "suffering" (see patience). In Middle English also of anyone who suffered patiently.