noun

• The act or process of making whole or entire.
• The process of combining with compatible elements in order to incorporate them.
• (society) The process of fitting into a community, notably applied to minorities.
• (calculus) The operation of finding the integral of a function.
• (biology) In evolution, the process by which the manifold is compacted into the relatively simple and permanent; supposed to alternate with differentiation as an agent in species' development.
• (US) Ellipsis of racial integration.. [The process of countering racial segregation by assimilating people of different races into a unified society.]