Any nanostructure, a member of the fullerene family, having graphene layers wrapped into perfect cylinders.

(inorganic chemistry) Alternative form of carbonyl chloride

A reduction in carbon dioxide emission by a third party purchased by a heavy carbon dioxide producer as part of carbon emissions trading.

(chiefly Britain) Alternative spelling of carbon oxysulfide

the process of making carbon prints

(inorganic chemistry) carbonyl sulfide

(chiefly Britain) Alternative spelling of carbon nanofiber

(inorganic chemistry) The gas C₃O₂, having a heterocumulene structure O=C=C=C=O

An instance of carbon emissions trading.

(astronomy) any of a class of red giant stars having a high proportion of carbon because of helium burning