1the action or process of integrating:economic and political integrationintegration of individual countries into trading blocs
the intermixing of people who were previously segregated:integration is the best hope for both black and white Americans
2 Mathematics the finding of an integral or integrals:integration of an ordinary differential equation [count noun]:mathematical integrations
3 Psychology the coordination of processes in the nervous system, including diverse sensory information and motor impulses:visuomotor integration
Psychoanalysis the process by which a well-balanced psyche becomes whole as the developing ego organizes the id, and the state which results or which treatment seeks to create by countering the fragmenting effect of defence mechanisms.
integration in other Oxford dictionaries
Definition of integration in the US English dictionary