Definitionen
1.NounA back gate, back door, side entrance, or other gateway distinct from the main entrance, especially in a city wall or fortification.
2.NounA separate or hidden way in or out of a place, situation etc.
3.NounA subterranean passage communicating between the parade and the main ditch, or between the ditches and the interior of the outworks.
4.AdjectiveSituated at the rear; posterior.