The Collaborative International Dictionary of English v.0.48:

Lithic \Lith"ic\ (l[i^]th"[i^]k), a. [Gr. liqiko`s of or
   belonging to stones, fr. li`qos stone: cf. F. lithique.]
   1. Of or pertaining to stone; as, lithic architecture.
      [1913 Webster]

   2. (Med.) Pertaining to the formation of uric-acid
      concretions (stone) in the bladder and other parts of the
      body; as, lithic diathesis.
      [1913 Webster]

   Lithic acid (Old Med. Chem.), uric acid. See Uric acid,
      under Uric.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Lithic \Lith"ic\, n. (Med.)
   A medicine which tends to prevent stone in the bladder.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Lithic \Lith"ic\, a. [From Lithium.] (Chem.)
   Pertaining to or denoting lithium or some of its compounds.
   --Frankland.
   [1913 Webster]

WordNet (r) 3.0 (2006):

lithic
    adj 1: of or containing lithium
    2: relating to or composed of stone; "lithic sandstone"