Definition from Wiktionary, the free dictionary
spiral (plural spirals)
- (geometry) A curve that is the locus of a point that rotates about a fixed point while continuously increasing its distance from that point.
- (informal) A helix.
Derived terms 
terms derived from spiral (noun)
spiral (not comparable)
- Helical, like a spiral
- (intransitive) To move along the path of a spiral or helix.
- The falling leaves spiralled down from the tree.
- (figuratively, intransitive) To increase continually.
- Her debts were spiralling out of control.
spiral m (plural spiraux)
Northern Sami