Definition:
A placebo is an inactive, fake, or "dummy" medication or treatment designed to resemble a drug or treatment and given in the same way. Any improvement in health that is measured, observed, or felt after the placebo is given is called the "placebo effect".
In clinical trials, a placebo may be given to one group of participants instead of the active drug or treatment in order to assess whether the latter is actually effective.
Pronunciation: pluh-see-bo
Examples: Although there have been preliminary studies on the effectiveness of reiki for various health conditions, there is a lack of well-designed, reproducible studies showing that reiki is more effective than a placebo.