The Collaborative International Dictionary of English v.0.48:

Hidrosis \Hi*dro"sis\, n. [Written also, but incorrectly,
   idrosis.] [NL., fr. Gr. ? to sweat, ? sweat.]
   1. (Physiol.) Excretion of sweat; perspiration.
      [Webster 1913 Suppl.]

   2. (Med.) Excessive perspiration; also, any skin disease
      characterized by abnormal perspiration.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

hidrosis
    n 1: the process of the sweat glands of the skin secreting a
         salty fluid; "perspiration is a homeostatic process" [syn:
         perspiration, sweating, diaphoresis, sudation,
         hidrosis]