Affixes

The more common form is chemo‑, as for example in chemotherapy, the chemical treatment of disease; chemoreceptor, a cell responsive to a chemical stimulus; chemosynthesis, the creation of chemical substances from inorganic material by bacteria; and chemoprophylaxis, the use of drugs to prevent disease. Two examples using chemi‑ are chemiluminescence, light created chemically without heat, as fireflies do, and chemisorption, absorption of a substance held in place by chemical bonds.