Definition of: cement

(si·ment′) noun
1. Any substance, as a preparation of glue, red lead, or lime, the hardening of which causes objects between which it is applied to adhere firmly.
2. Any compound or substance applied in the form of a mortar and used for producing a hard and stony, smooth, waterproof surface, coating, filling, or lining, as for a floor or cistern. Ordinary cement is made by heating limestone and clay, or a natural rock containing both materials in right proportions. When it will harden under water, it is called hydraulic cement.
3. That which serves to bind together persons or interests; bond of union.
4. Metall. a A finely divided metal obtained by precipitation: cement silver. b The substance in which iron is packed in the process of cementation.
5. Auriferous gravel held together by a clayey or silicic bond; also, the binding substance.
6. The glassy base of an igneous rock.
7. Cementum.
—Portland cement A hydraulic cement made by calcining limestone with clayey matter, such as chalk and river mud.
—v.t.
1. To unite or join with or as with cement.
2. To cover or coat with cement, as a cistern.
—v.i.
3. To become united by means of cement; cohere. [<OF ciment <L caementum rough stone, stone chip <caedere cut]
—ce·ment′er noun