GNU Collaborative International Dictionary of English

last match results

Found one definition

1.       
   Hormone (hôrˈmōn), n. [From Gr. ὁρμάειν to excite.]
   1. (Physiological Chem.) A chemical substance formed in one organ and carried in the circulation to another organ on which it exerts a specific effect on cells at a distance from the producing cells; “hormones produced in the brain may have effects on cells in distant parts of the body.”.
   
   [Webster 1913 Suppl. +PJC]
   
   
   2. (Physiological Chem.) a chemical substance, whether natural or synthetic, that functions like a hormone in a living organism.  “hormones may be more effective than their natural counterparts”.
   
   [PJC]
   
   
   3. (Bot.) A substance that controls growth rate or differentiation in plants; also called phytohormone.  The most well-known are the auxins that stimulate growth at the growing tips of plants, and control root formation and the dropping of leaves; and  the gibberellins, which are used in agriculture to promote plant growth.
   
   [PJC]