From Big Medical Encyclopedia

CHEMOTAXIS (srednevek. Arab al-kimiya; Greek chymeia and chemeia art of alloyage of metals + a taxis — motor reactions of freely moving vegetable and elementary animal organisms, and also cells (zoospores, spermatozoa, leukocytes, etc.) iod influence of chemical irritants; the chemotaxis can be positive (the movement is directed to a source of a chemical irritant) and negative (the movement is directed from a source of a chemical irritant) — see the Taxis.