Hand & Practice.

The word “Chiropractic” combines the Greek words cheir (hand) and praxis (practice) to describe a treatment done by hand. Hands-on therapy with an emphasis on spinal adjustment is central to chiropractic care. Chiropractic is based on the premise that the relationship between the body’s structure (primarily that of the spine) and its function (as coordinated by the nervous system) affects a person’s health.
National Institutes of Health, February 2012