The movement of water molecules through a selectively permeable membrane is called osmosis.

Here's a breakdown:

* Selectively permeable membrane: This type of membrane allows certain substances to pass through while blocking others. Cell membranes are selectively permeable, allowing water to pass through but often restricting larger molecules like sugars or proteins.

* Osmosis: This is the specific type of passive transport where water moves from a region of high water concentration (low solute concentration) to a region of low water concentration (high solute concentration) across a selectively permeable membrane.

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