[OED]: II. In extended use. A compartment; an enclosed space, cavity, or sac. 7b. gen. Any one of a number of small compartments or niches into which a larger structure is divided, as a compartment of a dovecote, a section of a drawer or cabinet, a pigeonhole, etc.;
14. Any one of a number of spaces into which a surface is divided by linear partitions: spec.; e.g. a. Archit. Any one of the spaces between the ribs of a vaulted roof.; b. Entomol. Any of the spaces between the nerves of the wings of insects.; 15. Biol. a. The fundamental, usually microscopic, structural and functional unit of all living organisms