Old English torr, from Latin turris "high structure" (cf. Old French tor, 11c.; Spanish, Italian torre "tower"), possibly from a pre-Indo-European Mediterranean language. Also borrowed separately 13c. as tour, from Old French tur. The modern spelling first recorded in 1520s. Meaning "lofty pile or mass" is recorded from mid-14c.
c.1400; see tower (n.). Related: Towered; towering.