Term Definition
OS&Y Valve 1 like
A valve that has external exposed threads which are held up by a yoke and which indicate whether the valve is open or closed
OSB 1 like
Oriented Strand Board
Oscillation 1 like
Moving or swinging back and forth repeatedly, from one extreme to another
Oscillograph 1 like
An instrument which records oscillations
Oscilloscope2 likes
A cathode ray tube that measures an electrical signal’s changing voltage
OSHA 1 like
Occupational Safety & Health Administration
Osmosis 0 likes
The process of a solvent passing through a semi-porous layer from a dilute solution into a more concentrated solution
Ottawa Sand 0 likes
A sand which is employed as the standard to test hydraulic cements with mortar test samples; naturally round particles of almost pure quartz
Out of Phase 0 likes
When a structure moves at a different frequency from the ground motion
Out of Square 0 likes
The deviation from a genuine square
Outdoor Exposure 0 likes
Plastic pipe which is not shielded from the impact of weather such as the sun, wind, rain or snow
Outfall Sewer 0 likes
A large sewer which spans between the collection site and the disposal site
Outlet 2 likes
The point into which appliances are plugged in order to draw electricity
An exit or way out
A store that sells products at a discount
Outlet Box1 like
outlet box
The receptacle which accommodates an electrical outlet and its attachments
Outline Lighting 0 likes
Positioning incandescent lamps or gaseous tubes so that they outline or highlight particular features of a building, such as its shape or door decoration
Outline Specifications 1 like
A shortened version of the specifications; usually created in design development or schematic design
Outrigger 0 likes
A rafter extension from the wall line; normally a smaller beam attached to a bigger rafter to produce a cornice or roof overhang
Outrigger Scaffold 1 like
Some scaffolding which is reinforced by outrigger beams which are cantilevered out from the structure
Outside Corner 0 likes
The place where two walls join and produce an external angle
Outside Four Inches 0 likes
The only level of stretcher courses on a wall face
Oven, Bake 0 likes
See Bake Oven
Oven, Convection4 likes
Oven Convection
See Convection Oven
Oven, Wall Mounted2 likes
oven, wall mounted
See Wall Mounted Oven
Ovendry Wood 0 likes
Wood which has been dried in a ventilated oven at 102 to 105° C; has a somewhat consistent weight
Overatomized 1 like
Scattered too finely due to overly atomized air pressure
Overcertification 0 likes
When an architect or engineer certifies more than the correct amount a contractor ought to be paid
Overcoat 1 like
Second or final coat
Overcurrent 0 likes
An electrical current that exceeds the wiring and devices’ capability
Overcurrent Device 2 likes
An apparatus that restricts a current to a preset number of amperes
Overflow 2 likes
An opening which permits rainwater overflow once it reaches a preset height, for roof drains it is usually 2 inches
Overflow System 1 like
The collection of water from the surface or a draw-off assembly
Overglaze Decoration 0 likes
Decoration made of ceramic or metal which is added and fired onto an already glazed surface of a ceramic
Overhand Work 1 like
A wall that is constructed from a scaffold positioned on only one side of the wall; the bricklayer leans over the wall to lay the brickwork on the other side
Overhang 0 likes
The part of a roof that protrudes over an external wall; See also Cornice
Overhang Beam 0 likes
A beam with one or both ends extending beyond the support; sustained by two or more supports
Overhead 1 like
Any indirect costs which are included in the total cost of sale; such costs are not directly connected to a unit of production
Overhead Concealed Closer 0 likes
A door closer that is hidden in the head frame; an arm connects to the door at the uppermost rail
Overhead Door 0 likes
A door that opens upward from the ground; frequently used in garages and warehouses
Overimprovement 1 like
An improvement to a property that is extravagant in size or cost when compared to similar properties; commonly used term when the improvement does not serve the property in the best way
Overlap 0 likes
When something is positioned in such a way that the edge is on top of and jutting out past the edge of another
Overlay 1 like
A drawing created by placing a thin piece of paper over another drawing
A thin layer of material bonded to one or both sides of a wood panel in order to provide a base for painting, either protective or decorative
Overlay Cabinet Construction 0 likes
A way to construct cabinets so that the doors and drawer fronts are positioned in front of the face frame
Overload 2 likes
Load that is larger than the amount that a particular system or machine is designed to support
Overload Protector3 likes
overload protector
Device that will prevent the operation of a unit when conditions become hazardous; operated by temperature, pressure or current; See Overcurrent Device
Oversized Brick 0 likes
A brick that has dimensions larger than 2-1/2 inches by 3-1/2 inches 7-1/2 inches
Overspray 0 likes
See Drift
Overvibration 0 likes
When freshly mixed concrete vibrates excessively when poured and causes separation
Ovolo 2 likes
A molding that is a quarter of a circle or ellipse
Owner 0 likes
A person or entity who signs the contract for a particular construction project
A person or entity with a title or interest in some portion of real property
Owner-Builder 1 like
An owner who undertakes a project and takes on the role of a general contractor
Owner-Construction Agreement 0 likes
Contract for a construction project that an owner and a contractor sign
Owner-Construction Management Agreement 2 likes
Contract for professional services that is signed by a construction manager and a client
Owners Overall Budget 2 likes
A budget that the owner creates detailing all the expenses of the project, including the purchase of land, building, financing, professional fees, and all accompanying costs
Owners Right to Stop Work 1 like
The owner can halt work on a construction project only if the contract allows for it and only for reasons agreed to in the contract
OX, OXO, OXXO 2 likes
Specifications for how sliding and fixed panels will be arranged in sliding glass doors and windows; X denotes a sliding panel; O denotes a fixed panel; See also XOOX , XO, XOO
Oxalic Acid2 likes
oxalic acid
An organic acid, toxic, typically white-colored and granular; used for breaking down iron rust stains on pool walls and floors, cleanse filter septa of iron rust, and as a bleach for wood
Oxidation 1 like
An action wherein a material chemically combines with oxygen
Oxidize 0 likes
To mix oxygen with another substance; to rust
Oxidized Sewage 0 likes
Sewage that is combined with oxygen; the process causes organic materials to stabilize
Oxidizing Flame 0 likes
A gas flame which has an oxidizing effect because it contains extra oxygen
Oxy-Acetylene 0 likes
An oxygen and acetylene mix that is employed as fuel for welding or cutting metals
Oxygen 0 likes
A gaseous element that has no color, taste odor, present in air, water, and nearly all minerals and organic matter; critical to biological life
Oxygen Cutting (OC) 1 like
Cutting processes in which metals react chemically with oxygen at elevated temperatures and are thereby severed or separated; employing a chemical flux or metal powder expedites the reaction
Oxygen-Acetylene Cutting 0 likes
A gas welding process in which a chemical reaction with oxygen and a base metal at elevated temperatures causes the metal to be cut; gas flames which result from acetylene burning with oxygen maintain the necessary temperature
Oxygen-Arc Cutting 4 likes
An oxygencutting process in which the metals react chemically with oxygen at elevated temperatures and are thereby cut; an arc positioned between an electrode and the base metal serves to maintain the required temperature
Ozone 1 like
A type of unstable oxygen, a light blue gas that has a powerful odor and strong oxidizing characteristics; employed in deodorizing, disinfecting, bleaching, and oxidizing
Product of the day


Detergent, alkali, acid, or another cleaning substance Solvent for cleaning paint equipment



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