placebo
Meaning of placebo: A placebo is an inactive substance or sham treatment used in research to distinguish a therapy's true effect from expectation and natural change.
Definition of placebo
A placebo is a substance, treatment, or procedure that has no direct pharmacological or physical effect on the condition being studied but is designed to be indistinguishable from the actual treatment under investigation. In a clinical trial, one group of participants receives the placebo while another receives the treatment being tested, allowing researchers to separate the treatment's real effect from changes that occur anyway, such as natural recovery or the influence of expectation.
The placebo effect refers to the measurable improvement some people experience after receiving a placebo, thought to arise from psychological expectation, conditioning, and the attention involved in receiving care, rather than from any active ingredient.
Placebo controlled trials remain a standard method for evaluating new treatments across many areas of medicine, though they are not used when withholding an effective treatment would be considered unethical.
Used in a sentence
Participants in the control group received a placebo rather than the active study medication.
Good to know
A placebo response is a genuine, measurable change in symptoms, not an indication that a person's original symptoms were imagined or absent.
Word origin
Where “placebo” comes from
Formed from Latin placebo, meaning I shall please, from placere, to please, a word later applied to a treatment given to satisfy a patient rather than to treat a condition directly.