any natural internal secretion, esp one that exerts an effect similar to a drug
Word origin
C20: from auto- + Greek akos cure + -oid
autacoid in American English
(ˈɔtəˌkɔɪd)
noun
1.
hormone
2.
any of a group of natural biochemicals, as serotonin, angiotensin, or histamine, that activate changes in the blood, nerves, etc., similar to those caused by drugs