Containing carbon; relating to or composed of carbon compounds.
From carbon + -ous (Latin suffix meaning 'full of' or 'characterized by'). This is an older adjectival form, less common than 'carbonaceous' in modern usage.
While 'carbonous' is technically correct, chemists prefer 'carbonaceous' because it's more specific—showing how scientific language evolves toward precision, even when it means abandoning older perfectly good words.
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