sawtooth

Short definition from Wiktionary

Noun

1. 1
   A tooth of a saw: any of its series of projections, each with a cutting edge.
2. 2
   A sawtooth wave.
3. 3
   Any of various pierid butterflies of the genus Prioneris.
4. 4
   A pattern whose living cell population reaches new peaks infinitely many times before dropping to a fixed value after each peak.