Answer:
[tex]\boxed {\boxed {\sf Osmosis}}[/tex]
Explanation:
Diffusion is the movement of particles from an area of high to low concentration. The solute (particles being dissolved in solvent) move.
Osmosis is similar to diffusion, except the solvent, which is often water, is moving. It moves across a semi-permeable membrane (certain molecules can pass, others cannot; an example is the cell membrane) from high to low solute concentration.
Therefore, the best term for diffusion of water across a semi-permeable membrane is osmosis.
