ETYM Latin vacuus empty: cf. French vacuole.
In biology, a fluid-filled, membrane-bound cavity inside a cell. It may be a reservoir for fluids that the cell will secrete to the outside, or may be filled with excretory products or essential nutrients that the cell needs to store.
In amebas (single-cell animals), vacuoles are sites for digestion of engulfed food particles. A plant cell usually has a large central vacuole to increase its surface area for food absorption.
A tiny cavity filled with fluid in the cytoplasm of a cell.