Cohesivity

Cohesivity refers to the quality or state of being cohesive—the tendency of elements of a system to stay connected and act as a whole. While often used interchangeably with cohesion or cohesiveness, cohesivity is a less common term and appears across disciplines to emphasize the integrative strength of a system rather than merely its component parts.

In social and organizational contexts, cohesivity describes the degree to which members of a group share common goals, norms, and identities, and cooperate toward collective outcomes. High cohesivity can facilitate communication, trust, and coordination, but excessive or exclusive cohesion may reduce critical discussion or dampen diversity.

In physical and materials science, cohesivity refers to the internal binding forces that hold a substance together. It is closely related to cohesion, cohesive energy, and surface tension, and explains why liquids form droplets and why solids resist deformation. Cohesivity underpins material properties such as strength, brittleness, and fracture behavior.

Measurement of cohesivity is context-specific. In sociology, it often relies on surveys and network analysis to assess social bonds and group solidarity. In physics and materials science, it involves thermodynamic quantities such as cohesive energy per mole or inter-molecular forces, and may be studied through spectroscopy, calorimetry, or mechanical testing.

The term is sometimes used as a synonym for cohesion or cohesiveness, though many sources prefer those terms in technical writing. See also: cohesion, cohesive energy, social cohesion, group dynamics.