Answer
The zigzag random motion of particles in the liquid arising due to the collision of particles is called the Brownian motion.
Work Step by Step
The collision of microscopic particles suspended in either liquid or gas makes the particles travel in a random zigzag path. This phenomenon is known as the Brownian motion.
According to Einstein, the random motion of particles is because of the extra energy associated with the particulate matter, due to which, the particles collide with each other. It could be concluded that matter comprises of constituent particles.