Glossary

Overview#

CAD vocabulary is a barrier for beginners because the same words are used loosely. This glossary defines the terms used throughout the guide, grouped by topic and then alphabetically within each group. Definitions are short on purpose; the linked guide pages go deeper. Terms are defined as Fusion uses them, which sometimes differs from general engineering usage.

Where to find it#

The glossary is a reference page, so you read it rather than operate it. Inside Fusion, hover tooltips and the Help menu provide official definitions. Autodesk's online Help (search "Autodesk Fusion help") is the authoritative source when your version's behavior differs.

Interface and file management#

• Application Bar: the strip at the top with the Data Panel toggle, New, Open, Save, Undo and Redo.
• Autodesk Account: your web account that holds licenses and entitlements.
• Browser: the left-side tree listing documents settings, named views, origin, bodies, components, sketches, and joints.
• Canvas: the 3D graphics area where you work.
• Data Panel: the cloud file browser that shows hubs, projects, folders, and designs.
• Design (document): a file of type Fusion Design that stores geometry, timeline, and parameters.
• Document Settings: per-file units, default orientation, and related options.
• Home view: the saved default orientation that the ViewCube Home button returns to.
• Hub: a top-level cloud container that holds projects; may be personal or team.
• Marking menu: the radial menu that opens when you right-click and hold.
• Milestone: a labeled version that you flag as important in a design's history.
• Navigation Bar: the bottom toolbar with Orbit, Pan, Zoom, Look At, and display settings.
• Preferences: the application-wide settings dialog reached from your profile.
• Project: a folder-like cloud container inside a hub that groups designs and members.
• S menu: the popup opened with the S key that searches commands.
• Toolbar: the row of command buttons that changes with the workspace and tab.
• Version: a saved state of a design, created each time you save.
• ViewCube: the interactive cube at the corner of the canvas used for orbiting and standard views.
• Workspace: a mode with its own toolbar, such as Design, Manufacture, Drawing, or Electronics.

Sketching#

• Closed profile: a loop of connected curves that can be extruded into a solid.
• Coincident: a constraint that makes two points, or a point and a curve, share location.
• Collinear: a constraint that places two lines along the same infinite line.
• Concentric: a constraint that gives two circles or arcs the same center.
• Constraint: a geometric rule, such as tangent or horizontal, that limits how sketch geometry can move.
• Construction geometry: reference lines and curves that do not form profiles.
• Dimension: a numeric value that fixes the size or position of sketch geometry.
• Driven dimension: a dimension that reports a value rather than controlling it.
• Fixed: a constraint that locks a point or curve in space.
• Fully constrained: a sketch whose geometry is completely defined, usually shown in black.
• Under-constrained: a sketch with remaining freedom, normally shown in blue.
• Over-constrained: a sketch with redundant or conflicting constraints.
• Fit point spline: a spline that passes through the points you place.
• Control point spline: a spline shaped by an external control polygon.
• Include 3D geometry: bringing a model edge into a sketch as a live link.
• Inference: automatic constraint detection while drawing.
• Offset (sketch): creating a parallel copy of connected curves at a distance.
• Origin: the point where the X, Y, and Z axes meet.
• Profile: a closed region of a sketch ready to be used by a modeling command.
• Project: creating sketch geometry from another body's edge, face, or sketch.
• Sketch plane: the flat plane or planar face on which a sketch lives.
• Sketch Palette: the panel with sketch options such as Look At, Slice, and Show Profile.
• Slice: a view option that cuts away geometry in front of the sketch plane.
• Symmetry (constraint): a rule that mirrors two points about a line.
• Tangent: a constraint that makes curves meet smoothly.
• Trim: removing the part of a curve up to its intersections.
• Unprojected geometry: sketch geometry that has lost its link to its source.

Solid modeling#

• B-Rep (boundary representation): a model described by its bounding faces, edges, and vertices.
• Body: a single solid or surface object, not yet a component.
• Boolean operation: joining, cutting, or intersecting bodies.
• Boss: a protruding cylindrical feature, often with a hole, used for fasteners.
• Chamfer: a straight bevel across an edge.
• Combine: a Boolean command with Join, Cut, and Intersect modes.
• Coil: a spiral solid or surface, used for springs and threads.
• Cut (operation): removing material, for example an extrude cut.
• Draft: an angled taper on faces for mold release.
• Edge: the curve where two faces meet.
• Extent: how far an extrude or similar command goes, such as Distance, To Object, or All.
• Extrude: pushing a profile along a direction to create volume.
• Face: a bounded surface region of a body.
• Feature: one modeling operation that appears as an item in the timeline.
• Fillet: a rounded edge.
• Hole: a drilled-style cut, with options like counterbore and countersink.
• Join (operation): merging new geometry with an existing body.
• Loft: a smooth transition between two or more profiles.
• Mirror: reflecting geometry across a plane.
• New Body (operation): creating a separate body instead of merging.
• Offset plane: a construction plane parallel to another at a distance.
• Pattern: copying a feature or body in a rectangular, circular, or path arrangement.
• Press Pull: a direct-editing command that offsets faces or extrudes profiles.
• Revolve: rotating a profile about an axis.
• Shell: hollowing a body, leaving a wall thickness.
• Solid: a closed volume with thickness; a body that holds mass.
• Sweep: moving a profile along a path.
• Thread: a modeled or cosmetic helical feature on a cylinder or hole.
• Vertex: a point where edges meet.

Parametric design and the timeline#

• Associativity: the property that dependent features update when the original changes.
• Parametric Modeling Mode / Direct Modeling Mode: whether a design records a timeline (parametric) or not (direct). Switch it by right-clicking the top-level component in the Browser.
• Configuration: a variant of a design with different parameter values or suppressed features.
• Dependency: a relationship in which one feature needs another to exist.
• Derive: bringing geometry from another design in as a linked body.
• Direct modeling: editing geometry without a recorded history.
• Expression: a formula in a parameter, such as width / 2.
• Feature failure: a timeline item that cannot compute and shows an error or warning.
• Group (timeline): a folder in the timeline that bundles features.
• Parametric modeling: building a model from dimensions and relationships that you can change later.
• Parameter: a named value that can drive dimensions and expressions.
• Roll back: moving the timeline marker to an earlier point.
• Suppress: temporarily make a feature and its dependent features unavailable without deleting it; they are not displayed in the canvas and are dimmed in the timeline (right-click > Suppress Features).
• Timeline: the bar at the bottom showing the order of features.
• User parameter: a parameter you create, as opposed to one created by a dimension.

Components and assemblies#

• As-built joint: a joint that keeps components where they already are.
• Assembly: a collection of components positioned and connected together.
• Bottom-up design: building parts separately, then assembling them.
• Bill of materials (BOM): a list of parts and quantities.
• Capture Position: saving the current joint positions as a timeline step.
• Component: a container that can hold bodies, sketches, joints, and other components.
• Contact set: a definition of which components collide during motion.
• External reference: a link from one design to a component stored in another file.
• Ground: fixing a component in space so it cannot move.
• Joint: a relationship that positions two components and defines how they can move.
• Joint origin: a point on a component used to place a joint.
• Motion link: a ratio that ties the motion of two joints together.
• Motion study: kinematic motion analysis based on joints (Autodesk help: Motion Study reference).
• Rigid group: a set of components that move as one.
• Top-down design: laying out an assembly from a master sketch or body, then deriving parts.

Surface, form, and mesh#

• Continuity: how smoothly two surfaces meet, ranked G0 (position), G1 (tangent), G2 (curvature), G3.
• Crease: a sharp edge on a Form body.
• Curvature comb: a visual analysis that shows how curvature varies along a curve.
• Form body: a T-spline body edited through control cages.
• Mesh body: a model made of triangles, as in STL or OBJ files.
• Patch: a surface that fills a boundary.
• Quadball: a Form primitive derived from a sphere with quadrilateral faces.
• Reduce (mesh): lowering the triangle count.
• Remesh: rebuilding a mesh for more uniform triangles.
• Stitch: sewing surfaces together along common edges, possibly making a solid.
• Surface: a body with zero thickness.
• T-spline: a subdivision-style surface technology that supports local refinement.
• Thicken: giving a surface a thickness to create a solid.
• Trim (surface): cutting a surface with another surface or curve.
• Zebra analysis: displaying stripes on a surface to judge reflection smoothness.

Manufacturing and fabrication#

• Bend radius: the inner radius of a sheet metal bend.
• Bend allowance: the arc length of the neutral axis through a bend.
• CAM: computer-aided manufacturing, which generates toolpaths.
• DFM (design for manufacture): shaping a design to be easy to produce.
• DXF: an exchange format used for flat 2D profiles and laser or waterjet cutting.
• Flat pattern: the unfolded layout of a sheet metal part.
• G-code: machine instructions produced by a post processor.
• K-factor: the ratio that locates the neutral axis in a bend.
• Post processor: a script that converts toolpaths to a specific machine's G-code.
• Rib: a thin supporting wall in a plastic or cast part.
• Setup (Manufacture): the definition of stock, work coordinate system, and model.
• Sheet metal rule: thickness, bend radius, and relief settings applied to a part.
• Snap fit: a flexible latch feature for plastic parts.
• STEP: a neutral solid-model exchange format.
• STL: a mesh format used for 3D printing.
• Toolpath: the path a tool follows to cut material.
• Wall thickness: the thickness of plastic or shell walls.

Rendering, animation, and drawings#

• Appearance: the visual look (color, finish) applied to a body.
• Decal: an image placed on a surface.
• Depth of field: blur that simulates camera focus.
• Environment: the lighting backdrop for a render.
• Exploded view: a view that separates components along paths.
• In-canvas render: rendering inside the Fusion window using your computer.
• Material (physical): properties such as density that affect mass and simulation.
• Cloud render: rendering on Autodesk servers, which can consume cloud credits.
• Storyboard: the animation timeline made of scenes and actions.
• Balloon: a numbered callout on a drawing that matches a parts-list row.
• Base view: the first view placed on a drawing sheet.
• Drawing template: a sheet size and title block starting point.
• GD&T: geometric dimensioning and tolerancing symbols.
• Parts list: a table of components with quantities.
• Projected view: a view derived from an existing view.
• Section view: a cutaway view through a plane.
• Sheet (drawing): a page in a drawing file.
• Title block: the information box on a drawing sheet.

Simulation, generative design, and electronics#

• Boundary condition: a constraint or load applied to a model in simulation.
• Buckling: sudden sideways failure under compression.
• Cloud credits (tokens): a unit consumed by cloud solves and some extensions.
• Contact (simulation): a rule that describes how touching bodies interact.
• Factor of safety: the ratio of material strength to calculated stress.
• Generative design: an automated process that explores many shapes against goals.
• Mesh (simulation): the finite elements into which a model is divided.
• Safety factor plot: a result visualization showing factor of safety.
• Stress (von Mises): a combined stress value used to judge yield.
• ERC (electrical rules check): a schematic check for connection errors.
• DRC (design rules check): a board check against clearances and widths.
• Footprint: the pad pattern of a part on a PCB.
• Gerber: the standard fabrication output for PCB layers.
• Net: an electrical connection between pins.
• Package: the physical outline and pad layout of a device.
• Symbol: the schematic graphic of a device.
• Via: a plated hole connecting PCB layers.

Licensing and cloud#

• Extension: a separately licensed add-on capability.
• Entitlement: a record that your account is licensed for a product.
• Fusion archive (.f3z): a local file containing a design and its references.
• Offline mode: working without a live connection for a limited time.
• Personal use: the free non-commercial license path.
• Read-only (inactive document): a design that is viewable but not editable under document limits.
• Startup license: a license for early-stage businesses.
• Team hub: a shared hub for collaboration under a paid plan.

Tips and pitfalls#

Tip: When a term appears with two meanings, check the context. "Component" in Fusion is a structural container, not simply "a part".

Warning: "Body" and "component" are routinely confused, and the confusion causes assembly problems. Read the Components vs bodies page before building multi-part designs.

Tip: Many terms differ from other CAD tools. For example, what other systems call a "part file" might be a single component in a Fusion design.

Practice exercise#

1. Choose ten terms from this page that you could not define before reading.
2. For each, find the matching command or interface element in Fusion.
3. Write a one-sentence definition in your own words and compare it to the entry here.

Expected result: you can explain the difference between a body, a component, a feature, and a parameter without hesitation.

Related#

• Commands index (this section)
• FAQ (this section)
• User interface tour (Getting Started)
• The timeline (Parametric Design)