| alexo-, alex-, alexi- (Greek: defend, protect, ward off, keep off).alexeteric: Protective against infection or poison.
 alexidine: An antibacterial substance.
 alexin: 1. A defensive substance in normal serum that destroys bacteria and other cells. alexipharmac, 1. Warding off the ill effects of a poison. 2. A name for a class of substances found in blood-serum, having the capacity of destroying bacteria, etc., and thus guarding against infection. 2. An antidote or remedy for poisoning. alexipharmic: Antidotal; an antidote.
 alexipyretic: A substance that reduces fever; antipyretic.
 phytoalexin: Any substance that is produced by plant tissues in response to contact with a parasite and specifically inhibits the growth of that parasite. The term was originally defined with regard to fungal parasites only, but in 1956 it was extended to cover all parasites [According to the Oxford English Dictionary].
 Alexander: alexicacon: alexikakon: alexipharmac: alexipharmacal: Alexis: alexiteric: alexitery: alexocyte: |