The term organic has different meanings (depending on the context):

In chemistry, "organic" refers to a chemical compound based on a hydrocarbon, i.e. a chain or a ring of carbon atoms onto which hydrogen atoms are bonded.

In agriculture, "organic" refers to a production system that excludes or limits the use of chemicals.

In chemistry, the often used description 'based on living things' is no longer approriate since synthetic organic chemicals can now be made. Over 8 million organic compounds are now known to man and this figure continues to rise.

In agriculture, crop rotation and animal manure can be used to maintain soil productivity in the place of fertilisers. Careful management reduces the need for pesticides, nutritional supplements and medicines.