biochar

noun

bio·​char ¦bī-(ˌ)o-¦chär 

: a form of charcoal that is produced by exposing organic waste matter (such as wood chips, crop residue, or manure) to heat in a low-oxygen environment and that is used especially as a soil amendment

… the US could convert huge amounts of logging and agricultural leftovers into biochar, and even grow crops just for that purpose.

—Josh Harkinson, Mother Jones, November/December 2008

… biochar holds such promise as an inexpensive and highly effective way to sequester carbon in soil.

—Al Gore, Our Choice: A Plan to Solve the Climate Crisis, 2009

Word History

First Known Use

1995, in the meaning defined above

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