1. A naturally abundant nonmetallic element that occurs in many inorganic and in all organic compounds, exists freely as graphite and diamond and as a constituent of coal, limestone, and petroleum, and is capable of chemical self-bonding to form an enormous number of chemically, biologically, and commercially important molecules. atomic number 6; atomic weight 12.011; sublimation point above 3,500°C; boiling point 4,827°C; specific gravity of amorphous carbon 1.8 to 2.1, of diamond 3.15 to 3.53, of graphite 1.9 to 2.3; valence 2, 3, 4. see table at element.
2. A sheet of carbon paper.
3. A carbon copy.
4. electricity either of two rods through which current flows to form an arc, as in lighting or welding.
5. electricity A carbonaceous electrode in an electric cell.

1. the chemical element (symbol C) with an atomic number of 6.
2. A sheet of carbon paper.
3. A carbon copy.
4. A fossil fuel that is made of impure carbon such as coal or charcoal.
5. carbon dioxide, in the context of global warming and climate change.

1. an elementary substance, not metallic in its nature, which is present in all organic compounds. atomic weight 11.97. symbol C. it is combustible, and forms the base of lampblack and charcoal, and enters largely into mineral coals. in its pure crystallized state it constitutes the diamond, the hardest of known substances, occuring in monometric crystals like the octahedron, etc. another modification is graphite, or blacklead, and in this it is soft, and occurs in hexagonal prisms or tables. when united with oxygen it forms carbon dioxide, commonly called carbonic acid, or carbonic oxide, according to the proportions of the oxygen; when united with hydrogen, it forms various compounds called hydrocarbons. compare diamond, and graphite.
2. A carbon rod or pencil used in an arc lamp; also, a plate or piece of carbon used as one of the elements of a voltaic battery.
3. a sheet of carbon paper.
4. a carbon copy.

1. to put carbons in (an arc lamp).
2. chemical symbol, C; atomic weight, 11.97. an element found in nature in two distinct forms: the diamond, which is extremely hard, of high specific gravity (3.5), usually colorless and transparent, with brilliant adamantine luster, and crystallizes in octahedrons; and graphite, which is very soft, of low specific gravity , black and opaque, with metallic luster, and crystallizes in hexagonal plates. see diamond and graphite.
3. the form of the diamond generally called carbonado; the black diamond.
4. in electric lighting, a carbon-point (see below).

1. a copy made with carbon paper
2. an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
3. a thin paper coated on one side with a dark waxy substance (often containing carbon); used to transfer characters from the original to an under sheet of paper