Wordnet 3.0
NOUN (2)
1. 
 the trade of planning the layout and furnishings of an architectural interior; 
[syn: interior decoration, interior design]
2.  the branch of architecture dealing with the selection and organization of furnishings for an architectural interior; 
WordNet (r) 3.0 (2006):
interior design
    n 1: the trade of planning the layout and furnishings of an
         architectural interior [syn: interior decoration,
         interior design]
    2: the branch of architecture dealing with the selection and
       organization of furnishings for an architectural interior