Could you clarify what you mean by ‘meaning’ here?
If you are asking for the purpose or ”goal’ – there is none. It is an ongoing continuous process of adaptiation and refinement with no end point of its own.
If you mean a definition – the standard one is
‘Evolution is the change in the genetic composition of a population during successive generations, as a result of natural selection acting on the genetic variation among individuals, and resulting in the development of new species.’
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