adj. 25B6; adjective
an inveterate gambler : CONFIRMED, hardened, incorrigible, addicted, compulsive, obsessive; informal pathological.
an inveterate Democrat : STAUNCH, steadfast, committed, devoted, dedicated, dyed-in-the-wool, out-and-out, diehard.
mankind's inveterate stupidity : INGRAINED, deep-seated, deep-rooted, entrenched, ineradicable, incurable.