se·cre·tion 1 
(sĭ-krēshən)
(sĭ-krēshən)n.
1. The process of secreting a substance, especially one that is not a waste, from the blood or cells: secretion of hormones; secretion of milk by the mammary glands.
2. A substance, such as saliva, mucus, tears, bile, or a hormone, that is secreted.
[French sécrétion, from Old French, separation, from Latin sēcrētiō, sēcrētiōn-, from sēcrētus, past participle of sēcernere, to set aside; see SECERN.]
se·cretion·ar′y (-shə-nĕr′ē) adj.