endocrine

(noun) the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect. Synonyms: hormone, internal secretion.

(noun) any of the glands of the endocrine system that secrete hormones directly into the bloodstream. Synonyms: endocrine gland, ductless gland.

(adj) of or belonging to endocrine glands or their secretions. Synonyms: endocrine (vs. exocrine), endocrinal. Example: "Endocrine system."