early 15c., "pertaining to music; tuneful, harmonious; adept at making music," from Middle French musical (14c.) and directly from Medieval Latin musicalis, from Latin musica (see music). Musical box is from 1829. Children's game musical chairs is attested from 1877, hence use of musical as a modifier meaning "changing rapidly from one to another possessor" (1924). Related: Musically.

"theatrical piece in which music figures prominently," 1937, from musical, adj. in musical play. Earlier as a noun it meant "musical instrument" (c.1500), "musical performance" (1570s); "musical party" (1823, a sense now in musicale).