Cĕll1, n.
n. [Lat. cella, akin to celare, to hide, conceal; Pr., It., & Pg. cella, Sp. celda.]
Sense 1. A very small and close apartment, as in a prison or a monastery. “The heroic confessor in his cell.” Macaulay.
Sense 2. Any small, closed cavity, or hollow place.
Sense 3. (Arch.) (a.) The inclosed space or chamber within the walls of an ancient temple. (b.) A hollow space between the ribs of a vaulted roof. Oxf. Gloss.
Sense 4. (Organic Structures.) A minute, inclosed space or sac, filled with fluid, making up the cellular tissue of plants, and of many parts of animals, and originating the parts by their growth and reproduction; the constituent element of all plants and animals (though not universal for all parts of such structure), much as a crystalline molecule is the element of a crystal. In the simplest plants and animals (as the infusoria), one single cell constitutes the complete individual, such species being called unicellular plants or animals.
Cell-development (called also cell-genesis, cell-formation, and the cytogenesis), the evolution of cells in organic growth by a process of reproduction, under the following forms: (a.) By spontaneous duplication, when a cell multiplies by a subdivision of itself into two halves, and this goes on successively; it is the most common mode, the cells either completely separating, as in the multiplication of infusoria, and in embryo development, or forming a continuous united line, as in the growth of common plants, and also in animal structure. (b.) By endogenous nuclear fission, when there is a subdivision of the nucleus of a cell, and thus new cells form within a parent cell. (c.) By endogenous multiplication without fission, when the granules of a cell change to distinct cells, with all their functions. (d.) By the evolution of cells in a plastic fluid, or blastema, without parent cells to originate them. — Germ-cell, the primordial cell in the egg, through whose development the perfect individual results; it is seldom alone, but usually surrounded with other albuminous material for its nutrition. — Gland-cell, one of the productive cells in a gland, which, as they form, are filled, by their own secreting action, with the peculiar fluid of the gland, and burst to discharge it, new ones continually rising. — Nucleated cell, one having a distinct nucleus: sometimes the nucleus contains a nucleus called the nucleolus. Dana.