germ-free
adjEtymology From germ + -free.
1
Without any (especially harmful) microorganisms; aseptic.
2
Sciences Specifically, pertaining to an animal with no microorganisms living in or on it, used in gnotobiotic research.
- It is worth being cautious: many studies show associations rather than cause and effect, and some are based only on studies in germ-free mice and have not been explored in humans.2018, Nicola Davis, The Guardian, 256 March: