The Collaborative International Dictionary of English v.0.48:

Deliquescent \Del`i*ques"cent\, a. [L. deliquescens, -entis, p.
   pr. of deliquescere: cf. F. d['e]liquescent.]
   1. Dissolving; liquefying by contact with the air; capable of
      attracting moisture from the atmosphere and becoming
      liquid; as, deliquescent salts.
      [1913 Webster]

   2. (Bot.) Branching so that the stem is lost in branches, as
      in most deciduous trees. --Gray.
      [1913 Webster]

WordNet (r) 3.0 (2006):

deliquescent
    adj 1: (especially of certain salts) becoming liquid by
           absorbing moisture from the air

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "deliquescent":
   contractive, declining, decoagulated, decreasing, decrescendo,
   decrescent, diminishing, diminuendo, dwindling, in solution,
   in suspension, languishing, lessening, liquefied, liquescent,
   melted, molten, on the wane, reductive, subsiding, thawed,
   unclotted, waning