Source : Webster's Revised Unabridged Dictionary (1913)

Sinecure \Si`ne*cure\, n. [L. sine without + cura care, LL., a
   cure. See {Cure}.]
   1. An ecclesiastical benefice without the care of souls.
      --Ayliffe.

   2. Any office or position which requires or involves little
      or no responsibility, labor, or active service.

            A lucrative sinecure in the Excise.   --Macaulay.

Sinecure \Si"ne*cure\, v. t.
   To put or place in a sinecure.

Source : WordNet®

sinecure
     n 1: a benefice to which no spiritual or pastoral duties are
          attached
     2: an office that involves minimal duties