The Collaborative International Dictionary of English v.0.48:

Catarrh \Ca*tarrh"\, n. [L. catarrhus, Gr. ?, ?, a running down,
   rheum, fr. ?; kata` down + ? to flow. See Stream.] (Med.)
   An inflammatory affection of any mucous membrane, in which
   there are congestion, swelling, and an altertion in the
   quantity and quality of mucus secreted; as, catarrh of the
   stomach; catarrh of the bladder.
   [1913 Webster]

   Note: In America, the term catarrh is applied especially to a
         chronic inflammation of, and hypersecretion fron, the
         membranes of the nose or air passages; in England, to
         an acute influenza, resulting a cold, and attended with
         cough, thirst, lassitude, and watery eyes; also, to the
         cold itself.
         [1913 Webster]

WordNet (r) 3.0 (2006):

catarrh
    n 1: inflammation of the nose and throat with increased
         production of mucus