closeness

Closeness is the state or quality of being near or emotionally connected. The term is used in multiple fields to describe nearness in space, time, social relationships, or similarity of attributes.

In physical terms, closeness refers to spatial proximity—how near objects, places, or people are to one another. Proximity can influence interaction, travel efficiency, and access to resources.

Mathematically, closeness is tied to proximity via a distance function. In metric spaces, two points are close if their distance is small; the concept underlies limits, neighborhoods, and convergence.

In psychology and sociology, closeness describes perceived emotional proximity to others and the strength of social bonds. Closeness is affected by communication, shared experiences, and trust, and it contributes to social support and well-being. Researchers measure closeness with self-report scales and observational methods.

In other domains, closeness can refer to lexical or cultural proximity—similarity of language, ideas, or customs—reflecting how alike or connected groups are.