democritus

noun

1. the Laughing Philosopher, c460–370 b.c., Greek philosopher.

noun

1. ?460–?370 bc, Greek philosopher who developed the atomist theory of matter of his teacher, LeucippusSee also atomism

1. Greek philosopher who developed one of the first atomist theories of the universe. Democritus believed that the world consists of an infinite number of very small particles whose different characteristics and combinations account for the different qualities of all matter.