Are yams and sweet potatoes the same?
1550s, from Middle French spiral, from Medieval Latin spiralis "winding, coiling" (mid-13c.), from Latin spira "coil," from Greek speira "coil, twist, wreath," from PIE *sper- "to turn, twist." Spiral galaxy first attested 1913.
1726 (implied in spiraled), from spiral (n.). Transferred and figurative sense by 1922. Related: Spiraling.
1650s, from spiral (adj.). U.S. football sense is from 1896.
spiral spi·ral (spī'rəl)
Coiling or developing around an axis in a constantly changing series of planes; helical. n.
A structure in the shape of a coil. v. spi·raled or spi·ralled, spi·ral·ing or spi·ral·ling, spi·rals or spi·rals
To take the form or course of a spiral.
plane curve that, in general, winds around a point while moving ever farther from the point. Many kinds of spiral are known, the first dating from the days of ancient Greece. The curves are observed in nature, and human beings have used them in machines and in ornament, notably architectural-for example, the whorl in an Ionic capital. The two most famous spirals are described below.