Wordnet 3.0
ADJECTIVE (2)
1. 
 (of experimental animals) raised under sterile conditions; 
- Example: "axenic conditions"- Example: "germfree animals"2. 
 (used of cultures of microorganisms) completely free from other organisms; 
- Example: "an axenic culture"
The Collaborative International Dictionary of English v.0.48:
axenic \axenic\ adj.
   1. raised under sterile conditions; -- of experimental
      animals; as, axenic conditions.
      [WordNet 1.5]
   2. pure or completely free of the presence of other
      organisms; -- used of cultures of microorganisms; as, an
      axenic culture.
   Syn: uncontaminated; germ-free.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
axenic
    adj 1: (of experimental animals) raised under sterile
           conditions; "axenic conditions"; "germfree animals"
    2: (used of cultures of microorganisms) completely free from
       other organisms; "an axenic culture"