bio·​sig·​na·​ture | \ ¦bī-(ˌ)ō-¦sig-nə-ˌchu̇r+ How to pronounce biosignature (audio) \
plural biosignatures

Definition of biosignature

: something (such as a chemical compound, isotope, or cellular component) that indicates or suggests the presence of a biological process indicative of life This will help astronomers learn to recognize “biosignatures”—clues that a planet's atmosphere has been influenced by life.— Karen Schmidt, New Scientist, 2 July 2005 … the potential of the microbes to become fossils and serve as “biosignatures” for researchers seeking signs of early life in the remnants of ancient volcanism and hydrothermal activity on Earth—and, particularly, on Mars.— David Perlman, San Francisco Chronicle, 21 Apr. 2005

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First Known Use of biosignature

1995, in the meaning defined above

History and Etymology for biosignature

bi- entry 2 + signature

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Time Traveler for biosignature

The first known use of biosignature was in 1995

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