established If you use established to describe something such as an organization, you mean that it is officially recognized or generally approved of because it has existed for a long time. adj usu ADJ n Their religious adherence is not to the established church., ...the established names of Paris fashion.
well-established , well established
If you say that something is well-established, you mean that it has been in existence for quite a long time and is successful. adj
The University has a well-established tradition of welcoming postgraduate students from overseas., ...well-established companies such as Compaq and Olivetti.