ˈvakyəˌwōl noun
( -s )
Etymology: French, literally, small vacuum, from Latin vacuum + French -ole
1. : a small space in the tissues of an organism containing air or fluid
2. : a cavity in the cytoplasm of a cell that is bounded by a distinct membrane, that is characteristic of plant cells and protozoans but may occur in higher animals, that in higher plant cells occupies most of the space of the cell, contains cell sap, and is often interpreted as a droplet of fluid enclosed by a membrane rather than as a vacuity, and that in protozoans is one of the most prominent organelles, performs various digestive, excretory, hydrostatic, and secretory functions, and may be either a transitory or an essentially permanent part of the protoplast — see contractile vacuole , food vacuole , tonoplast ; amoeba illustration, cell illustration