- unblocked frog
- A frog in a railroad switch which has not been blocked or filled in such manner as to prevent a person's foot or shoe from being caught and wedged in the frog. Southern Pacific Co. v Seley, 152 US 145, 150, 38 L Ed 391, 393, 14 S Ct 530; Union Pacific Railway Co. v James, 163 US 485, 41 L Ed 236, 16 S Ct 1109.
Ballentine's law dictionary. Anderson, W.S.. 1998.