The answers are "higher water potential" and "lower water potential".
Osmosis is a kind of way that water molecules move down a water potential gradient through a partially permeable membrane. Note that osmosis is only referring to the movement of water molecules, but not other substances, and, a partially permeable membrane must be present. Which means, the membrane can select what substances can go in and out. Examples are such as cell membrane.
High water potential is a result of high water concentration. Water potential refers to the tendency of water molecules to move. The steeper the water potential gradient is (larger water conc. difference), the faster the water molecules will flow to the region of lower water potential.
Examples of osmosis in real life include when plants absorb water. Root hair cells cytoplasms have a lower water potential than that of the soil, therefore, water molecules from the soil will flow to the root hair cells. This is how most plants absorb water.
