CAD Jargon

As with most sectors in the technical industry when it comes to CAD there is a lot of jargon floating about, so we’ve compiled a small glossary of CAD jargon and what it all means. A lot of these terms are also common in other IT related fields.


A computer program, but often more specifically a CAD application, capable of carrying out complex tasks specific to a CAD project. CAD Applications often run alongside CAD software in order to automate or perform specialized tasks.


Often drawn automatically in various shapes and sizes, arrowheads are the part of a dimension which points to an object or extension line.

Bezier Curve

This is a curve which is defined by endpoints, tangent lines and control points, the shape of the curve can be altered by altering the length and angle of the tangent lines.


A pixel based graphic or image.


Computer-aided design, the use of computers to assist in the creation, modification, analysis or optimization of a design.


Computer aided design and drafting.


A diagonal line used to connect the points of two intersecting objects.


A group of objects which can be manipulated simultaneously.


A tool used to limit drawings to a specific point, line or angle, such as snap-to-grid.


A numerical system used to locate a particular point within a drawing. These are 2 or 3 numbers, x and y in 2D drawings and x, y and z in 3D drawings.


A temporary coordinate which can be used as a snap or reference point in a drawing.

Drawing Database

A list of all of the objects within a drawing, as well as other parameters and definition points.


Created and used by Autodesk, a DXF file is an ascii text file which describes drawing data and settings to translate drawings between programs.


The virtual environment within a CAD program which includes all drawing settings, units, tools, etc.


A command used to break objects apart in to their component pieces.

Extension Line

A line extended from a measured line or object to the dimension line, showing the measured distance.


An arc connecting endpoints of two intersecting lines or objects.


The filling of a defined area with solid colour.


The typographic style of text.


A drawing tool consisting of regularly spaces dots or lines which make alignment and drawing of objects easier. Can be used in combination with snap to grid to lock all drawing to grid points only.


A collection of objects which can be edited or manipulated as one object.


A complex object defined by a series of points or a bordering object, filling the defined area with a repeating pattern of lines.


Layers are used for organisational purposes for the ease of drawing, viewing and editing. Layers can be named and have default properties associated with them.


A line with an arrowhead and attached text pointing at another object.


An object defined by two endpoints.


A drawing object with a single reference point and no physical dimension.


A sequence of commands recorded and saved for easy playback, very useful for saving time.

Major Axis

The longer axis of an ellipse.

Manual Entry

Entering points manually by typing co-ordinates rather than clicking within the workspace.


Objects contained inside of other objects.

Object Handles

The handles that appear when an object is selected, used to allow stretching, rotating or moving of objects.


The distance between two objects.


The point in a drawing with the co-ordinates of 0,0.


The process of altering the drawing view by moving the viewpoint laterally relative to the drawing.


A complex object composed of three or more straight lines in a closed figure.