A nowhere dense set is a set whose closure has empty interior.

Every intersection of countably many dense open sets is dense.

(Any other dense countable set may be used equally well.)

These last two examples illustrate the fact that the boundary of a dense set with empty interior is its closure.

Every closed nowhere dense set is the boundary of an open set.

A nowhere dense set is not necessarily negligible in every sense.

An object is represented by a dense set of points or viewer-facing discs holding lighting information.

In addition there is a dense set of constructible angles of infinite order.

An alternative definition of dense set in the case of metric spaces is the following.

In geometric terms, one has to work with functions defined on some open, dense set of a given variety.