Synonyms of established

1 Syllable

set, known, tight, stock

2 Syllables

well-set, lawful, tightest, seated, steadfast, based, stablest, vested, old-line, proved, skintight, parked, jural, mainstream, standard, trusted, rooted, brick-wall, stocker, settled, legit, fixed, stable, stabler, founded, tighter

3 Syllables

prevailing, orthodox, regular, enforced, ordained, situated, deep-rooted, deep-seated, entrenched, ingrained, verified, card-carrying, official, accepted, long-standing, secure, prevalent, permanent, doctrinal, stabile, installed

4 Syllables

surefire, customary, unshakable, buttoned-down, close-fitting, ordinary, never-failing, unmovable, unmistaken, traditional, ritualistic

5 Syllables

well-established, irreversible, long-established, unrepealable, unquestionable, unreversible, irrevocable, uncontestable, unremarkable

6 Syllables

incontrovertible, verificatory