What is the meaning of Established?

simple past and past participle of establish

Having been in existence for a long time and therefore recognized and generally accepted.

Of a religion, church etc.: formally recognized by a state as being official within that area.

Of any social or economic entity: part of the establishment (groups with socioeconomic power).

(Model, procedure, disease) Explicitly defined, described or recognized as a reference.

Source: wiktionary.org