- Not contaminated by or associated with any other living organisms. Usually used in reference to pure cultures of microorganisms that are completely free of the presence of other organisms.
- raised under sterile conditions; -- of experimental animals.
- pure or completely free of the presence of other organisms; -- used of cultures of microorganisms.
- Containing only a single <xref>species</xref> of <xref>microorganism</xref>. For example, an "axenic culture" means that a pure sample of the organism in question has been grown.
- <xref>Isolated</xref> from <xref>organisms</xref> of any other <xref>species</xref>
- (of experimental animals) raised under sterile conditions
- (used of cultures of microorganisms) completely free from other organisms