agrichar

agri- +‎ char, a US trademark.

agrichar (uncountable)

1. Biochar produced by a slow pyrolysis process.
   • 2009 June 22, Tyler Hamilton, “Sole option is to adapt, climate author says”, in Toronto Star‎:

     I've written before about biochar, or agrichar, or charcoal, or just plain char — it's all pretty much the same.

• chiragra