Inventor and CAD glossary

How to use this glossary

The terms are listed A to Z. Where a term is taught in the course, the entry links to that lesson so you can see it used on a real part. If a word in a lesson is unfamiliar, search this page with Ctrl+F.

Inventor uses some everyday words in a narrow sense. “Constraint”, for example, means one thing in a sketch and something related but different in an assembly, so both meanings have their own entry.

Terms A–Z

Aligned dimension

A dimension measured parallel to a sloped edge or between two points, instead of horizontally or vertically. Use it when you need the true length of a line that is not square to the sketch axes.Taught in Lesson 7, Lesson 12

Assembly (.iam)

A file that brings parts and sub-assemblies together and positions them with constraints. It stores links to the part files, not copies, so a change to a part shows up in every assembly that uses it.Taught in Lesson 9, Lesson 10

Base view

The first view you place on a drawing sheet, taken straight from the 3D model. Projected, section and detail views are created from it, and all of them update when the model changes.Taught in Lesson 11

Bend radius

The inside radius of a sheet metal bend. It comes from the sheet metal rule and changes the length of the flat pattern, so it should match the tooling the workshop will use.Taught in Lesson 8

Bill of materials (BOM) and parts list

The bill of materials lists every component in an assembly with its quantity. On a drawing, the parts list shows the same information as a table, numbered to match the item balloons.Taught in Lesson 10

Center mark

The cross drawn at the centre of a circle or arc in a drawing view. Holes are dimensioned from their center marks, so add them before you dimension.Taught in Lesson 12

Centerline and centerline bisector

A chain line through the axis of a round feature or along a line of symmetry. A centerline bisector is drawn halfway between two edges, for example along the middle of a shaft seen from the side.Taught in Lesson 12

Chamfer

An angled cut that removes a sharp edge. It is usually defined by a distance and an angle (for example 1 × 45°) or by two distances.Taught in Lesson 6

Circular pattern

Repeats a feature or sketch geometry a set number of times around an axis, over a full 360° or a chosen angle. Edit the original and every copy follows.Taught in Lesson 6

Coincident constraint

Joins a point to another point, a line or a curve, so the two stay together when the sketch changes.Taught in Lesson 3

Concentric constraint

Makes two circles or arcs share the same centre point, for example a hole and the boss around it.Taught in Lesson 3

Constraint (assembly)

A relationship between faces, edges, axes or points of two components that removes degrees of freedom. Inventor’s main ones are Mate, Flush, Angle, Tangent and Insert.Taught in Lesson 9, Lesson 10

Constraint (sketch)

A rule that controls sketch geometry. Geometric constraints set relationships such as parallel, tangent or equal; dimensions set sizes and distances. Together they decide how a sketch reacts when you change it.Taught in Lesson 2, Lesson 3

Construction geometry

Sketch lines, circles and arcs used only as references. They help you position other geometry but are ignored when you choose a profile for a feature.

Content Center

Inventor’s library of standard parts, such as screws, nuts, washers and bearings, built to standards like ISO and DIN. You place them into an assembly at the right size instead of modelling them yourself.Taught in Lesson 10

Degrees of freedom (DOF)

The ways a sketch entity or a component can still move. A free component in an assembly has six: three translations and three rotations. Every dimension or constraint you add removes one or more of them.Taught in Lesson 3, Lesson 9

Dimension style

A set of drawing rules for dimensions: text height, arrowheads, units, precision and how tolerances are shown. Styles live in the Style and Standard Editor; the DIN standard comes with DIN styles.Taught in Lesson 12

Driven dimension

A reference dimension that shows a value but does not control the geometry. Inventor puts it in brackets. You get one when you dimension geometry that is already fully constrained.

DWG and IDW drawings

Inventor can save a drawing in two formats. IDW is Inventor’s own drawing format; DWG is the AutoCAD format, which colleagues can also open in AutoCAD. Both stay linked to the 3D model.Taught in Lesson 11

End of Part marker

The marker at the bottom of a part’s model browser. Features below it are not calculated, so you can drag it upwards to see, or edit, the part as it was earlier in its history.

Equal constraint

Gives two circles the same radius or two lines the same length, so one dimension controls both.

Extrude

Adds depth to a closed sketch profile to create or remove material. You choose the distance, the direction (Default, Flipped, Symmetric or Asymmetric) and whether the result joins, cuts or intersects the existing solid.Taught in Lesson 1

Feature

One modelling operation stored in the browser, such as an extrusion, a hole, a fillet or a pattern. A part is a sequence of features, calculated from top to bottom.Taught in Lesson 1

Fillet

A rounded edge of constant radius. In a sketch, a fillet rounds the corner where two lines meet.Taught in Lesson 5

First-angle projection

The projection method used in Europe and on DIN/ISO drawings: the view from above is drawn below the front view, and the view from the left is drawn to the right of it. The DIN cheat sheet shows the layout.Taught in Lesson 11

Flange

A sheet metal wall bent up from an existing edge. You set its height, bend angle, width and position along the edge.Taught in Lesson 8

Flat pattern

The unfolded shape of a sheet metal part, used to cut the blank before it is bent. Inventor calculates it from the thickness, bend radius and unfold rule.Taught in Lesson 8

Flush constraint

An assembly constraint that makes two faces point the same way and lie in the same plane, or at a set offset, like two boards laid side by side.Taught in Lesson 9

Fully constrained

A sketch in which every point is fixed by dimensions and constraints, so nothing can move by accident. Inventor reports it in the status bar.Taught in Lesson 2

Grounded component

A component fixed in place in an assembly, with all six degrees of freedom removed. Usually the main part is grounded and everything else is constrained to it.Taught in Lesson 9

Hem

A sheet metal edge folded back on itself to stiffen it and remove the sharp edge. A double hem folds it twice.Taught in Lesson 8

Hidden lines

Edges that sit behind other material in a drawing view, shown as dashed lines. Turn them on when they make the part easier to read, not by default.Taught in Lesson 12

Hole and thread notes

Drawing annotations that read their data from the hole or thread feature, for example M10 × 1.25 – 6H, so the note always matches the model.Taught in Lesson 12

Hole feature

A placed feature for drilled, counterbored, countersunk, clearance and tapped holes in standard sizes. It is better than extruding a circle because the drawing can read its size and thread.Taught in Lesson 8, Lesson 12

Horizontal and vertical constraints

Make a line, or two points, line up with the sketch’s X or Y direction.Taught in Lesson 3

Inscribed and circumscribed polygon

An inscribed polygon fits inside a circle with its corners on the circle; a circumscribed polygon fits around the circle with its flat sides touching it. For a hexagon, inscribed sets the size across the corners and circumscribed sets it across the flats.Taught in Lesson 3

Insert constraint

An assembly constraint for round features such as a screw in a hole. It mates two faces and lines up the two axes in one step; Lock Rotation stops the part from spinning.Taught in Lesson 10

IPT (.ipt)

Inventor’s part file. It keeps the full feature history, so the part stays editable.Taught in Lesson 1

Isometric view

A pictorial view in which the three main axes appear 120° apart. On a drawing it helps the reader understand the shape at a glance.Taught in Lesson 11

Mate constraint

An assembly constraint that places two faces against each other, pointing in opposite directions, or lines up two axes, edges or points.Taught in Lesson 9

Mirror

Copies features or sketch geometry symmetrically about a plane or a line. The copy stays linked to the original.Taught in Lesson 4

Model browser

The panel on the left that lists a file’s sketches, features, work features and components in the order they were made. Double-click an item to edit it.Taught in Lesson 1

Motion constraint

An assembly constraint that links the movement of two components, for example two gears where one turns at a fixed ratio of the other (rotation–rotation).Taught in Lesson 10

Offset work plane

A work plane created parallel to an existing plane or face at a set distance, useful when there is no face where you need to sketch or mirror.Taught in Lesson 4

Origin

The default planes (XY, YZ, XZ), axes (X, Y, Z) and centre point that every part and assembly starts with. You find them in the Origin folder of the browser.Taught in Lesson 1

Parallel and perpendicular constraints

Keep two lines at the same angle (parallel) or at 90° to each other (perpendicular), whatever their length or position.Taught in Lesson 3

Parameters and equations

Every dimension in Inventor is a named parameter (d0, d1, …). You can type an expression such as 50/2 or d3*2 instead of a number, and the value updates when the dimension it refers to changes.Taught in Lesson 6

Parametric modelling

Modelling in which dimensions and relationships drive the geometry. Change a value and the model rebuilds to match, which is why a well-constrained sketch matters.Taught in Lesson 1

Profile

A closed loop of sketch geometry, such as a circle or a closed rectangle, that a feature can turn into a solid.Taught in Lesson 1, Lesson 2

Project Geometry

Copies edges, points or features from the model into the active sketch as reference geometry, so new sketch lines can be constrained to what is already there.Taught in Lesson 7

Projected view

A drawing view made from a base view by dragging up, down, sideways or diagonally. A diagonal projection gives an isometric view.Taught in Lesson 11

Rectangular pattern

Repeats a feature or sketch geometry in rows and columns along one or two directions.Taught in Lesson 4

Revolve

Creates a solid by turning a sketch profile around an axis. It is the natural choice for shafts, pulleys and other round parts.

Scale

The ratio between size on paper and real size: 1:1 is full size, 1:2 half size and 2:1 twice size. The main scale is written in the title block.Taught in Lesson 11

Section view

A drawing view that shows the part as if cut along a cutting plane. Cut material is hatched and the view is labelled with letters, such as A-A.Taught in Lesson 11

Sheet metal rule

A style that sets the thickness, bend radius, reliefs and unfold method of a sheet metal part. Change the rule and every feature that uses it updates.Taught in Lesson 8

Sketch

2D geometry drawn on a plane or a flat face. Almost every feature starts from one.Taught in Lesson 1

Status bar

The strip along the bottom of the Inventor window. While you sketch, it tells you how many dimensions are still needed, or that the sketch is fully constrained.Taught in Lesson 2

STEP (.stp, .step)

A neutral CAD exchange format. It carries the 3D shape so other CAD programs can read it, but not Inventor’s feature history.Taught in Lesson 1

Style and Standard Editor

The dialog where drawing standards and styles are kept: dimension, text, leader and hatch styles, plus units and the projection method.Taught in Lesson 12

Symmetric constraint

Makes two points or curves mirror images of each other about a line.

Tangent constraint

Makes a line and a curve, or two curves, touch at one point without crossing, so the shape flows smoothly from one to the other.Taught in Lesson 3, Lesson 5

Template

A starting file with units, standards and styles already set. In this course, Standard (DIN).ipt from the Metric folder gives you millimetres and DIN drawing standards.Taught in Lesson 1

Thread feature

Adds thread data to a cylindrical face or a hole, for example M10 × 1.25. Inventor shows it as a cosmetic thread and uses it for the thread note on the drawing, without modelling every turn.Taught in Lesson 6

Title block

The table in the lower-right corner of a drawing sheet with the part name, drawing number, scale, material, author and date.Taught in Lesson 11

Tolerance

How far a dimension may vary from its nominal size, written as 20 ±0.1, as limits, or as a fit such as Ø20 H7. Tighter tolerances cost more to make.Taught in Lesson 12

Trim

Removes the part of a sketch curve between intersections. It is how overlapping circles and lines become one clean profile.Taught in Lesson 5

Unfold and refold

Sheet metal tools that flatten selected bends so you can add features across them, then bend the part back again.Taught in Lesson 8

ViewCube

The cube in the top-right corner of the graphics window. Click a face, edge or corner to turn the model to that view; the house icon returns to the Home view.Taught in Lesson 1

Work plane, work axis and work point

Reference geometry you create when the origin and the model faces are not enough, for example a plane offset from a face or an axis through a cylinder.Taught in Lesson 4

Keep going

For the keys behind these tools, see the Inventor keyboard shortcuts. For line types, projection and tolerances on drawings, see the DIN drawing standards cheat sheet.