1550s, from Middle French spiral (16c.), from Medieval Latin spiralis "winding around a fixed center, coiling" (mid-13c.), from Latin spira "a coil, fold, twist, spiral," from Greek speira "a winding, a coil, twist, wreath, anything wound or coiled," from PIE *sper-ya-, from base *sper- (2) "to turn, twist." Related: Spirally. Spiral galaxy first attested 1913.