Psychiatry is different from psychology in that psychiatry is a branch of medicine aimed at treating mental illness whereas psychology is the science that studies the mental aspects of motivation and behavior.
Both words, however, come from a common Greek root psyche .
In ancient Greece psyche referred that ethereal aspect of ourselves that isn't our physical self. And also more literally to our breath, needed for life. By extension, this word for the fluttery breath of life became the Greek word for “butterfly.” In Greek mythology Psyche is also the name of a most beautiful mortal young woman with whom the young god Cupid falls in love. Cupid being the god of love this has a nice sort of “love of life” tone to it.
The cover of my book Carnal Knowledge has two images of the human body on it; one male, one female.
The male is Bacchus.
The female is that beautiful Greek Psyche.
Her image is actually a detail from a painting called The Awakening of Psyche by Guillaume Seignac.
It isn't shown in the detail on the book but here's a link to a more complete image where you can see that the lovely Psyche actually has butterfly wings sprouting out of her back. Returning to our word of the day, psyche meaning “soul” or “spirit” came into English in the 17th century during the renaissance when the most scholarly things always had something Latin or Greek about them.
The word psychology also appeared in English in the 17th century but psychiatry waited another hundred years before it appeared in print—this because there wasn't much thought of curing crazy people before that, mostly they were locked up in asylums. The ending of the word psychiatry is also from Greek and means “healing” whereas the end of psychology is from the Greek word logos which literally means “word”—which is why a logophile is a “word lover.” But logos also has to it the sense of “to speak,” “discuss” and “reason.” So the literal meaning of psychiatry is “spirit healing.” Breaking down psychology into its parts we get “spirit understanding.”
