bio·​mass | \ˈbī-ō-ˌmas \

Definition of biomass 

1 : the amount of living matter (as in a unit area or volume of habitat)

2 : plant materials and animal waste used especially as a source of fuel

Examples of biomass in a Sentence

Recent Examples on the Web

But the notion that biomass is carbon neutral is contentious among scientists. Dino Grandoni, Washington Post, "The Energy 202: Why Scott Pruitt's decision on burning wood is so high stakes," 24 Apr. 2018 The biomass, or mass of fish found in this area worldwide, is equivalent to a hundred times the Earth’s global catch of seafood, according to the New York Times. Brian J. Skerry, National Geographic, "Why Great White Sharks Hang Out in Warm Whirlpools," 19 June 2018 Humans only add up to about one ten-thousandth of the life on Earth, measured by the dry weight of the carbon that makes up the structure of all living things, also known as biomass. Seth Borenstein,, "The weight of the world: Pound for pound, humans just a tiny sliver of life," 22 May 2018 And although 2017 assessments by the U.S. Geological Survey found alewife biomass to be lowest on record (by bottom trawl) and fourth-lowest (by acoustic testing), the key forage fish is showing up on anglers' graphs and in salmon stomachs. Paul A. Smith, Milwaukee Journal Sentinel, "Larger salmon spicing up Lake Michigan catches this year," 23 June 2018 The first is bioenergy with carbon capture and sequestration (BECCS), which involves burning biomass (plants or biowaste) in a thermal power plant, capturing CO2 from the exhaust stream, and burying the CO2. David Roberts, Vox, "Sucking carbon out of the air won’t solve climate change," 14 June 2018 Fish biomass in the reefs surrounding rat-free islands was 50 percent greater than reefs near the invaders. Matt Simon, WIRED, "Rats! Coral Reefs Aren't Getting the Bird Poop They Need," 11 July 2018 Another study, which estimated biomass at various points in the Atlantic, found the highest levels in these warm-water eddies. Brian J. Skerry, National Geographic, "Why Great White Sharks Hang Out in Warm Whirlpools," 19 June 2018 To figure out the biomass of each creature, quantitative biologists spent 3 years combing the scientific literature. Elizabeth Pennisi, Science | AAAS, "Plants outweigh all other life on Earth," 21 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biomass.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of biomass

1931, in the meaning defined at sense 1

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Last Updated

28 Oct 2018

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The first known use of biomass was in 1931

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bio·​mass | \-ˌmas \

Medical Definition of biomass 

: the amount of living matter (as in a unit area or volume of habitat)

More from Merriam-Webster on biomass

See words that rhyme with biomass Encyclopedia article about biomass

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