adjective

1. circling around a central point in a flat, two-dimensional curve that constantly increases (or decreases) in size
2. circling around a central axis in a conical or cylindrical, three-dimensional curve

Etymology: ML spiralis < L spira, a coil < Gr speira: see spire

noun

1. a spiral curve occurring in a single plane
2. a spiral curve occurring in a series of planes; helix
3. something having a spiral form, as a wire for holding sheets in some notebooks
4. a spiral path or flight the descending spiral of a falling leaf
5. a section or segment of a spiral
6. a continuous, widening decrease or increase an inflationary spiral ending in financial collapse
7. ☆ Football a kick or pass in which the ball rotates on its longer axis as it moves through the air

intransitive verb spiraled -·raled or spiralled -·ralled, spiraling -·ral·ing or spiralling -·ral·ling

transitive verb