Source : Webster's Revised Unabridged Dictionary (1913)

Lukewarm \Luke"warm`\, a. [See {Luke}.]
   Moderately warm; neither cold nor hot; tepid; not ardent; not
   zealous; cool; indifferent. `` Lukewarm blood.'' --Spenser.
   `` Lukewarm patriots.'' --Addison.

         An obedience so lukewarm and languishing that it merits
         not the name of passion.                 --Dryden.
   -- {Luce"warm`ly}, adv. -- {Luce"warm`ness}, n.

Source : WordNet®

lukewarm
     adj 1: moderately warm; "he hates lukewarm coffee"; "tepid bath
            water" [syn: {tepid}]
     2: feeling or showing little interest or enthusiasm; "a
        halfhearted effort"; "gave only lukewarm support to the
        candidate" [syn: {halfhearted}]