The Collaborative International Dictionary of English v.0.48:

Devanagari \De`va*na"ga*ri\, n. [Skr. d[=e]van[=a]gar[imac];
   d[=e]va god + nagara city, i. e., divine city.]
   The script or characters in which Sanskrit and Hindi are
   written.
   [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

Devanagari
    n 1: a syllabic script used in writing Sanskrit and Hindi [syn:
         Devanagari, Devanagari script, Nagari, Nagari
         script]