What is the transfer of liquid between cell walls called?

The transfer of liquid between cell walls is referred to as osmosis. Osmosis is a specific type of passive transport that involves the movement of water molecules across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. This movement continues until there is equilibrium reached, meaning that the concentration of solute is balanced on both sides of the membrane.

In biological systems, such as in plant and animal cells, osmosis is crucial for maintaining cell turgidity and overall homeostasis. For instance, in plants, osmosis allows for the absorption of water from the soil, which then moves into the root cells and throughout the plant, enabling essential functions such as nutrient transport and photosynthesis.

While diffusion involves the movement of molecules from an area of higher concentration to an area of lower concentration, and evaporation pertains to the phase change of liquid to gas, these processes do not specifically refer to the transfer of liquid in relation to cell walls. Filtration involves separating solids from liquids through a barrier, which is a different process altogether. Therefore, osmosis is the correct term for the type of liquid transfer described in the question.