D defs.my
Entry 1 sense Webster, 1913

dunno

/(dŭn*nō")/ · dun·no · IPA /dəˈnoʊ/
01 phrase A slang shortening of I don't know or don't know; as, dunno where I lost my keys; Where'd he go? I dunno..
  1. 1.
    A slang shortening of I don't know or don't know; as, dunno where I lost my keys; Where'd he go? I dunno..