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

Word History


bi- entry 2 + signature

First Known Use

1995, in the meaning defined above

Time Traveler
The first known use of biosignature was in 1995

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Dictionary Entries Near biosignature

Cite this Entry

“Biosignature.” Dictionary, Merriam-Webster, Accessed 9 Dec. 2023.

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