'Jagger spring' definitions:

Definition of 'Jagger spring'

From: GCIDE

Jagger \Jag"ger\, n. [From 4th Jag.] One who, or that which, jags; specifically: (a) a jagging iron used for crimping pies, cakes, etc. (b) A toothed chisel. See Jag, v. t. [1913 Webster]
Jagger spring, a spring beneath a seat, and resting on cleats or blocks in the body of a vehicle. --Knight. [1913 Webster]