The Collaborative International Dictionary of English v.0.48:

Appurtenant \Ap*pur"te*nant\, a. [F. appartenant, p. pr. of
   appartenir. See Appurtenance.]
   Annexed or pertaining to some more important thing;
   accessory; incident; as, a right of way appurtenant to land
   or buildings. --Blackstone.
   [1913 Webster]

   Common appurtenant. (Law) See under Common, n.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Appurtenant \Ap*pur"te*nant\, n.
   Something which belongs or appertains to another thing; an
   appurtenance.
   [1913 Webster]

         Mysterious appurtenants and symbols of redemption.
                                                  --Coleridge.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Appertinent \Ap*per"ti*nent\, a.
   Belonging; appertaining. [Now usually written appurtenant.]
   --Coleridge.
   [1913 Webster]

WordNet (r) 3.0 (2006):

appurtenant
    adj 1: furnishing added support; "an ancillary pump"; "an
           adjuvant discipline to forms of mysticism"; "The mind and
           emotions are auxiliary to each other" [syn: accessory,
           adjunct, ancillary, adjuvant, appurtenant,
           auxiliary]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

APPURTENANT. Belonging to; pertaining to of right.