Center Bit 
Drill bit used to locate the precise center of a hole to be drilled. The sharp, small point, which extends from the cutting end focuses the force of the drill and bores a small hole. Also called a brad point bit, it eliminates the need for a center punch by preventing the bit from drifting off center. 

Center Drill 
Short shank drill designed to drill a shallow, flared hole in the end of a piece of metal, which will be turned in a lathe. The lathe tailstock center fits in the center-drilled hole in the metal. 

Center Gauge 
Also called a thread gauge, this template that has an internal V on one end and an External V on the other with two smaller V's on the side with each of them being precision ground and lapped. This gauge is used for setting tool bits in the tool post of the lathe, for checking the included angles of machine centers and checking the shapes of threading tool bits. 

Center Head 
V-shaped device, which is mounted on a ruler, very much the way a blade is on a combination square, and is placed against a circular object with the object is in the center of the V, which allows for measurement of the radius of the circular object. 

Center Hung Sash 
Widow sash that moves horizontally around suspension points in the center. 

Center Mullion 
The vertical piece of wood on the front of a cabinet that divides the opening into two parts. 

Center of Gravity 
The center point of any object where the mass is evenly distributed around. 

Center Punch 
Conical tipped punch of hardened steel, which is used to mark indentations in metal. 

Center-to-Center 
Measurement that goes from the centerline of one object to the centerline of another. 

Centerline 
Drawing line through the center of an object. 

Centers 
Distance between studs, which may be 16" or 24". Alternately, distance from the center of one faucet to the center of another, which may be 4", 6" or 8" between. 

Centigrade Scale 
Temperature scale that uses 100 division between the freezing point of water (0 degrees) and the boiling point of water (100 degrees). Centigrade temperatures are marked by the letter C, as in 40degrees C. 

Centimeter 
Metric system measurement of one one-hundredth (0.001) of a meter, which equals 0.3937 inch. 

Centiorari 
Writ issued by a superior court to a lower court requiring the latter to produce a record of the proceedings of a particular case for purposes of reviewing these proceedings to determine if there is a legal basis for an appeal hearing 

Central Air Conditioning 
Cold air, throughout the house, generated by an outside unit, connected to ductwork inside the house. 

Central Business District 
Primary business district of a city, which has the area's major governmental offices and professional and retail businesses. 

Central Heating System 
A heating system consisting of four different elements; heat producer, exchanger, distributor and controls. 1. The heat producer is usually a gas or oil burner with electric or coal heaters being infrequently used. 2. The exchanger is what the producer heats; a furnace if air is heated; a boiler if water or steam is heated. 3. The heat distributor distributes the heat. With a hot water system, the heated water is sent through the pipes by a circulator to converters or radiators that give off heat. Forced warm air system has air drawn into ducts by a large fan and forced out through warm air registers. With a steam heating systems, steam rises on its own to heat radiators, which then give off heat. 4. The control is normally a thermostat at one location but may also be several thermostats at various locations for zone control. 

Central Processing Unit (CPU) 
Computer section containing memory and processing circuitry for the operations controlled by the computer. 

Centrifugal 
Outward movement from the axis of rotation. 

Centrifugal Compressor 
Compressor that uses centrifugal force to compress gas by feeling it into a wheel with radial vanes. The wheel is then seal inside of a cylinder and spun. When the wheel rotates, the gas is thrown away from the wheel center. The outward spinning motion compresses the gas. 

Centrifugal Fan 
Fan that causes air to move outward in a direction perpendicular to direction o the air that enters the fan. 

Centrifugal Force 
Force that causes a mass to move away from the center of rotation. 

Centrifuge 
Machine, which spins and gives a centrifugal force to an attached object. Machine using centrifugal force and the difference in densities of material to separate those materials.

Centripedal
Inward movement toward the axis of rotation. 

Centroid 
Center mass of any object. 

Ceramic 
Item made from clay or a claylike material. 

Ceramic Color Glaze 
Opaque glaze of silica or similar material, which is fused onto the masonry at temperatures above 1500 degrees F. Control of the quality is by ASTM Standard C126 that ensures that specified requirements have been met. 

Ceramic Tile 
Kiln fired flat tile that is formed into shape from clay or other silicon materials such as sand or quartz. Available in a variety of shapes, sizes, colors and finishes they are used for countertops, floor and wall surfaces in kitchens, baths, etc. or in decorative places. Impervious to water, stain resistant and easy to clean they are useful in high traffic areas. Installed in evenly-spaced rows they are cemented to plywood and the joints are filled in with grout. 

Certificate 
Official, written documentation certifying that the fulfillment of certain requirements has occurred on a certain date. 

Certificate of Beneficial Interest 
Document stating that someone has an ownership interest but not direct control, in an asset, business or estate. 

Certificate of Deposit (CD)
Document representing that the bearer has a specified amount of money on deposit in a financial institution. 

Certificate of Deposit Index 
An index based on the interest rates on six-month CDs. Is often used to determine the interest rate on some adjustable rate mortgages. 

Certificate of Eligibility
Veterans Administration document verifying the eligibility of a veteran for a loan program. 

Certificate of Occupancy (CO)
Document issued by the building department of the town, stating that the house has met all of the building codes and is habitable. 

Certificate of Sale 
Document issued by the court at a judicial sale, entitling the purchaser to receive a deed once the court approves the purchase. 

Certificate of Title 
Attorney's opinion of the status of a title, which is attached to the abstract of title. 

Certification 
Written statement of the correctness and reliability of something; written permission to do something. 

Certified Assessment Evaluator (CAE) 
Credential awarded by the International Association of Assessing Officers to appraisers of real estate working for a government body. 

Certified Historic Structure 
Building recognized because of its history. 

Certified Property Manager (CPM) 
Professional certification given by the Institute of Real Estate Management. 

Certified Residential Broker (CRB) 
Certification granted by the Realtors National Marketing Institute. 

Certified Residential Specialist (CRS) 
Certification granted by the Realtors National Marketing Institute upon successful completion of an education program and the required residential sales experience. 

Cession Deed 
Deed used to transfer property rights to a governmental authority. 

Cess Pool 
Underground pit or tank used to store sewage. 

Cetane Number 
Comparison of the ignition quality of diesel fuel, Cetane and alpha -methyl-napthalene are both hydrocarbons but alpha-methyl-napthalene has very poor ignition quality while cetane has good ignition quality. After mixing them together, adjustment is made so that it has the same ignition quality as the diesel fuel being tested and the cetane number, given to the diesel fuel, is the percentage of cetane in the mixture. 

CFM 
Cubic feet per minute.