fuse plug

Short definition from Wiktionary

Noun

1. 1
   A component of an aircraft wheel held in place by a metal alloy with a low melting point, such that, if the wheel is severely overheated (for instance, by heavy braking), pressure is released from the wheel and tire/tyre in a controlled manner rather than risking an explosion of the wheel assembly.
2. 2
   A collapsible dam or levee designed to give way in extreme flood conditions in order to divert water away from more important water-control structures.