The Collaborative International Dictionary of English v.0.48:

Upholstery \Up*hol"ster*y\, n.
   The articles or goods supplied by upholsterers; the business
   or work of an upholsterer.
   [1913 Webster]

WordNet (r) 3.0 (2006):

upholstery
    n 1: covering (padding and springs and webbing and fabric) on a
         piece of furniture
    2: the craft of upholstering