'autacoid' originates from Neo-Latin/modern scientific formation ultimately drawing on Greek elements: 'autos' meaning 'self' and a component related to 'akos' meaning 'remedy' or 'cure', producing the sense of a 'self-remedy' or locally acting agent.

'autacoid' was coined in modern medical/scientific usage (early 20th century) from these Greek-derived combining forms and has been used in biomedical literature to denote locally acting mediators; it entered English scientific vocabulary with little phonological change and the plural form 'autacoids' follows regular English pluralization.

Initially formed with a literal sense of 'self-remedy' or 'local remedy', the term evolved in biomedical usage to mean 'a locally acting biological mediator' rather than a therapeutic remedy; this narrower physiological meaning is now standard.