c.1600, "building set apart for scientific experiments," from Medieval Latin laboratorium "a place for labor or work," from Latin laboratus, past participle of laborare "to work" (see labor (n.)). Figurative use by 1660s.
laboratory lab·o·ra·to·ry (lāb'rə-tôr'ē)
A room or building equipped for scientific research.
A place where drugs and chemicals are manufactured.
A place for practice, observation, or testing.