Tightness

Tightness may refer to:

In mathematics,
 * Tightness of (a collection of) measures is a concept in measure (and probability), theory in mathematics
 * Tightness (topology) is also a cardinal function used in general topology

In economics,
 * Tightness refers to the degree to which the number of unemployed workers exceed the number of posted job vacancies (or vice versa).
 * Market tightness, a point in time where it is very difficult to invest, but it is far easier to sell or to remove investments in return of monetary rewards

In other fields,
 * Tightness of a rope indicates the rope is under tension
 * Tightness of a sealing means it is impermeable, that it seals well
 * Tightness is the art of being 'tight' (i.e., stingy or miserly)
 * Tightness can refer to something being cool