Vehicle theft prevention device

Wikipedia Word definitions in Wikipedia
An immobiliser or immobilizer is an electronic security device fitted to an automobile that prevents the engine from running unless the correct key (or other token) is present. This prevents the car from being " hot wired " after entry has been achieved ...

Wiktionary Word definitions in Wiktionary
n. 1 Something or someone that immobilises. 2 # (cx medicine English) A splint. 3 # An electronic security device fitted to an automobile that prevents the engine from running unless the correct key (or other token) is present.