| A | B |
|---|
| Acute Triangle | A triangle that contains only angles that are less than 90 degrees. |
| Angle | The amount of rotation needed to bring one line or plane into coincidence with another, generally measured in radians or degrees. |
| Area | The number of square units required to cover a surface. |
| Axis | 1. An imaginary line through a body, about which it rotates. 2. An imaginary line about which a regular figure is symmetrically arranged. 3. A fixed reference line for the measurement of coordinates. |
| Cartesian Coordinate System | A rectangular coordinate system created by three mutually perpendicular coordinate axes, commonly labeled X, Y, and Z. |
| Chamfer | A small angled surface formed between two surfaces. |
| Circle | The set of all points in a plane at a given distance from a given point in the plane. |
| Circumscribe | 1. A triangle located round a polygon such as a circle. 2 To draw a figure around another, touching it at points but not cutting it. |
| Computer-Aided Design or Computer-Aided Drafting (CAD) | 1. For design, the use of a computer to assist in the process of designing a part, circuit, building, etc. 2. For drafting, the use of a computer to assist in the process of creating, storing, retrieving, modifying, plotting, and communicating a technical drawing. |
| Counterbore | A cylindrical recess around a hole, usually to receive a bolt head or nut. |
| Countersink | A conical-shaped recess around a hole, often used to receive a tapered screw. |
| Cylinder | A solid composed of two congruent circles in parallel planes, their interiors, and all the line segments parallel to the axis with endpoints on the two circles. |
| Diameter | A straight line passing from side to side through the center of a circle or sphere. |
| Ellipse | A regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points is constant, or resulting when a cone is cut by an oblique plane which does not intersect the base. |
| Extrusion | 1. A manufacturing process that forces material through a shaped opening. 2. A modeling process that creates a three-dimensional form by defining a closed two-dimensional shape and a length. |
| Geometric Constraint | Constant, non-numerical relationships between the parts of a geometric figure. Examples include parallelism, perpendicularity, and concentricity. |
| Inscribe | To draw a figure within another so that their boundaries touch but do not intersect. |
| Mass | The amount of matter an object contains. |
| Numeric Constraint | A number value, or algebraic equation that is used to control the size or location of a geometric figure. |
| Obtuse Triangle | A triangle with one angle that is greater than 90 degrees. |
| Origin | A fixed point from which coordinates are measured. |
| Parallelogram | A quadrilateral polygon with opposite sides parallel. |
| Pattern | A repeated decorative design. |
| Pi | The numerical value of the ratio of the circumference of a circle to its diameter of approximately 3.14159. |
| Plane | A flat surface on which a straight line joining any two points would wholly lie. |
| Polygon | A closed geometric figure in a plane formed by connecting line segements endpoint to endpoint with each segment intersecting exactly two others. Polygons are classified by the number of sides they have, such as a triangle has three sides, a quadrilateral has four sides, and a pentagon has five sides. |
| Prism | A solid geometric figure whose two ends are similar, equal, and parallel rectilinear figures, and whose sides are parallelograms. |
| Quadrilateral | A four-sided polygon. |
| Radius | A straight line from the center to the circumference of a circle or sphere. |
| Rectangle | A parallelogram with 90 degree angles. A square is also a rectangle. |
| Regular Polygon | A polygon with equal angles and equal sides. |
| Revolution | Creating a 3D solid or surface by revolving a 2D shape about an axis. |
| Right Triangle | A triangle that has a 90 degree angle. |
| Rotation | Turning around an axis or center point. |
| Round | A rounded exterior blend between two surfaces. |
| Solid | A three-dimensional body or geometric figure. |
| Solid Modeling | A type of 3D CAD modeling that represents the volume of an object, not just its lines and surfaces. This allows for analysis of the object’s mass properties. |
| Space | 1. The dimensions of height, depth, and width within which all things exist and move. 2. A free or unoccupied area or expanse. |
| Square | A regular polygon with four equal sides and four 90 degree angles. |
| Surface Area | 1. The sum of all the areas of all the faces or surfaces that enclose a solid. 2. The sum of all the areas of all surfaces of a solid. |
| Tap | To cut internal threads. |
| Taper | Gradual diminution of width or thickness in an elongated object. |
| Three-Dimensional | Having the dimensions of height, width, and depth. |
| Triangle | A polygon with three sides. |
| Two-Dimensional | Having the dimensions of height and width, height and depth, or width and depth only. |
| Vertex | Each angular point of a polygon, polyhedron, or other figure. |
| Volume | The amount of space occupied by a substance or object or enclosed within a container. |
| Working Drawings | Drawings that convey all of the information needed to manufacture and assemble a design. |
