Vacuole n. : A small air cell, or globular space, in the interior of organic cells, either containing air, or a pellucid watery liquid, or some special chemical secretions of the cell protoplasm.

Example:
What role does the Vacuole play in the energy balance of a cell (both animal and plant)?

Taxonomy
vacuole, cell, central vacuole, organelle, plants, membrane, Vacuolation, ions, cell membrane, proteins, cytoplasm, food vacuole, fungal vacuole, free encyclopedia, protists, turgor pressure, cell wall, acidic.

Defination from the web:
vacuole is to maintain turgor pressure against the cell wall. ... Turgor pressure exerted by the vacuole is also essential in supporting plants in an upright position. ...