passe partout

CIDE DICTIONARY

passe partout, n. [F., from passer to pass + partout everywhere.].

That by which one can pass anywhere; a safe-conduct. Dryden. [1913 Webster]
A master key; a latchkey. [1913 Webster]
A light picture frame or mat of cardboard, wood, or the like, usually put between the picture and the glass, and sometimes serving for several pictures. [1913 Webster]
A strip of adhesive paper or gummed tape used to mount a picture between a piece of glass and a backing. [WordNet 1.5]
The method of mounting a picture between a piece of glass and a backing, using a passe-partout{4}. [PJC]

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