'Maginot Line' definitions:

Definition of 'Maginot Line'

(from WordNet)
noun
A fortification built before World War II to protect France's eastern border; initially considered to be impregnable, it was easily overrun by the German army in 1940

Definition of 'Maginot line'

From: GCIDE
  • Maginot line \Maginot line\ prop. n. A line of fortifications built before World War II to protect France's eastern border. [WordNet 1.5]