inveterate

adj

1. Firmly established from having been around for a long time; of long standing.

   “Near-synonyms: deep-rooted, ingrained, ineradicable, indelible, radicated, chronic, permanent”

   “an inveterate disease”

   “an inveterate habit”

   “a Heaven's radiance of justice, prophetic, clearly of Heaven, discernible behind all these confused worldwide entanglements, of Landlord interests, Manufacturing interests, Tory-Whig interests, and who knows what other interests, expediencies, vested interests, established possessions, inveterate Dilettantisms, Midas-eared Mammonism.”

   “In Montpelier, where this prison stands, the inveterate prejudice against prisoners has been swept away.”

2. Having had a habit (usually a bad habit) for a long time.

   “Near-synonyms: hardened, chronic, dyed-in-the-wool”

   “an inveterate idler;   an inveterate gambler;   an inveterate smoker”

   “an inveterate traveller”

   “"Say no more," interrupted Henrietta: "the very mention of that inveterate gossip accounts for every thing. Do let me, my dear Mrs. Courtenaye," and she took her hand with a kindness that was irresistible, "let me warn you against allowing your happiness to be the sport of a woman like that;...”

   “[S]he offered kisses to a stranger so confidingly that the most inveterate bachelor relented.”

3. Malignant; virulent; spiteful.

   “A man of mild manners can form no idea of inveterate revenge or cruelty[…]”

   “1765–70, Henry Brooke, The Fool of Quality; or, The History of Henry, Earl of Moreland This his lordship perused with a countenance, and scrutiny, apparently inveterate.”

verb

1. (obsolete)To fix and settle after a long time; to entrench.

   “"the vulgar conceived that now there was an end given, and a consummation to superstitious prophecies, the belief of fools, but the talk sometimes of wise men, and to an ancient tacit expectation which had by tradition been infused and inveterated into men's minds."”

   “"none of these Princes do use to maintaine any armies together, which are annex'd and inveterated with the governments of the provinces, as were the armies of the Roman Empire. "”

   “The foregoing elements of disunion are inveterated by the constituent formation of our national legislature. In the French chambers the members are all Frenchmen ; but our members of Congress are effectively Georgians, New-Yorkers, Carolinians, Pennsylvanians, &c.”