Tools menu > Isolate Selection

Right-click to open the quad menu. > Display (upper-right) quadrant > Isolate Selection

Keyboard > Alt + Q

The Isolate Selection tool lets you edit a single object or selection set of objects while hiding the rest of the scene on a temporary basis. This guards against selecting other objects while working on a single selection. It allows you to focus on the objects you need to see, without the visual distraction of the surroundings. It also reduces the performance overhead that can come from displaying other objects in the viewports.

When an isolated selection includes multiple objects, you can select a subset of these, and choose Isolate Selection once again. This isolates the subset. However, clicking Exit Isolation unhides the entire scene. You can’t “step back” through individual levels of isolation.

Note: Isolate Selection works only at the object level. You can’t choose it while at the sub-object level. If you go to a sub-object level while working with an isolated object, you can click Exit Isolation, but you can’t isolate sub-objects.

Tip: You can also use Isolate Unselected to isolate all of the unselected objects in your scene.