What does cambium Mean answer

a layer of delicate meristematic tissue between the inner bark or phloem and the wood or xylem, which produces new phloem on the outside and new xylem on the inside in stems, roots, etc., originating all secondary growth in plants and forming the annual rings of wood.

Cambium - a cellular plant tissue from which phloem, xylem, or cork grows by division, resulting (in woody plants) in secondary thickening.