Microgravity
Microgravity is a condition of apparent near-weightlessness. People and objects float because they are falling together, not because gravity has disappeared.
Technical meaning
An orbiting spacecraft, its crew, and everything inside it are in continuous free fall around Earth. Because they share nearly the same acceleration, objects exert very little support force on one another and appear weightless. Small residual accelerations remain from drag, rotations, vibrations, thruster firings, gravity gradients, and other disturbances.
Why it matters
Microgravity changes fluid behavior, combustion, heat transfer, human physiology, material processing, and the way tools and equipment must be designed. It is both an operating environment and a commercial research service.