To drive off or scatter in different directions: The police dispersed the crowd. To strew or distribute widely: The airplane dispersed the leaflets over the city. To cause to vanish or disappear. See Synonyms at scatter. To disseminate (knowledge, for example). To separate (light) into spectral rays. To distribute (particles) evenly throughout a medium. To separate and move in different directions; scatter: The crowd dispersed once the concert ended. To break up and vanish; dissipate: The storm clouds had dispersed by noon.