See inveterate in Webster's New World Roget's A-Z Thesaurus II
adjective
Firmly established by long standing:
confirmed, deep-rooted, deep-seated, entrenched, hard-shell, ineradicable, ingrained, irradicable, set1, settled. See continueSubject to a disease or habit for a long time:
chronic, confirmed, habitual, habituated. See continue
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