spiral

Short definition from Wiktionary

Noun

1. 1
   A curve that is the locus of a point that rotates about a fixed point while continuously increasing its distance from that point.
2. 2
   A helix.
3. 3
   A self-sustaining process with a lot of momentum involved, so it is difficult to accelerate or stop it at once.
4. 4
   A section of track that forms a circle and crosses over itself, used for gaining height in mountainous territory.

Adjective

1. 1
   Helical, like a spiral.

Verb

1. 1
   To move along the path of a spiral or helix.
2. 2
   To cause something to spiral.
3. 3
   To increase continually.