What term describes when a particle is carried or picked up by a second particle?

The concept of entrainment refers to the process by which one particle is carried or picked up by a second particle, often occurring in dynamic environments such as fluid systems. This term is frequently used in various scientific contexts, including meteorology, geology, and fluid dynamics. In these scenarios, entrainment typically describes how particles in a flow (like sediments in water or aerosols in the atmosphere) become incorporated into the larger moving mass, thereby influencing behaviors such as transportation and sedimentation.

Suspension would imply that particles are maintained in a fluid medium but doesn't necessarily highlight the action of being picked up by another particle. Advection refers to the transport of substances through the movement of the fluid itself rather than the interaction between individual particles. Deposition, on the other hand, describes the process where particles settle out of a fluid and accumulate, which is the opposite of being carried away. Thus, entrainment captures the essence of the interaction and transport mechanism where one particle actively lifts and transports another.