Synonyms for established

modified

1. In a firm position

   secure, fixed, stable, set, entrenched, settled, well-established, rooted, vested, officially recognized, old-line, deep-rooted, ingrained, unshakable; see also permanent 2, traditional 2.

2. Set up to endure

   endowed, founded, organized, instituted, set up, realized, originated, chartered, incorporated, settled, inaugurated, codified, systematized, ratified, equipped, brought into existence, conceived, produced, begun, initiated, completed, finished.

   Antonyms temporary*, unsound, insolvent.

3. Conclusively proved

   verified, approved, guaranteed, endorsed, demonstrated, determined, confirmed, substantiated, accepted, assured, concluded, closed, authenticated, corroborated, found out, achieved, upheld, certain, ascertained, valid, validated, identified, proved, undeniable, sure, objectified.

   Antonyms false*, invalidated, untrue.