noun.1. a pharmacologically inert compound which is frequently delivered as a control in testing new drugs. Placebos utilized in double-blind trials might be active or dummies. Previously, placebos were utilized from time to time as psychotherapeutic or diagnostic agents. 2. any psychological or medical remediation or intervention which is thought to be inert, thereby rendering it valuable as a control condition against which to compare the remediation or intervention of interest.
PLACEBO: "Generally, the last 4-7 pills in hormonal birth control packets are placebo pills."