
The longer a word of French provenance spends in the English-speaking world, the greater the chances of its complete naturalization. Thus, Anglophones invariably pronounce the ‘t’ in ‘adroit’, a word which made its debut in 1617, in a (less than entirely flattering) description of the Roman emperor Caligula.1
Of tall stature, bright hair, the top of his head bald, his forehead hight, large, and wrinkled; his looks fixed and stern; his eyes sunk in his head; hollow temples; a pale complexion; a great belly, neck, and legs; his body all cover’d with hair; he was a great master of musick, and had an extraordinary fine voice; he was very adroit and dexterous at handling his arms, dancing, and cleverly turning a chariot.
For the same reason, the evil twin of ‘adroit’, which took its sweet time crossing the Channel, has yet to shed all of its Gallic features. Thus, while some denizens of the Anglosphere pronounce ‘maladroit’ in a way that harmonizes with ‘adroit’, others say it in a manner worthy of Hercule Poirot.
Marvelous to say, the other antonym of ‘adroit’ managed to sidestep the whole question of pronunciation and do so, I might add, adroitly. Thus, from the very start, the English pronunciation of ‘gauche' differed little from the way that French people spoke the word.
For Further Reading:
Abbé de Fourcroy (Thomas Brown, translator) A New and Easy Method to Understand the Roman History (London: R. Wellington, 1617) pages 121-122
Interesting topic! Domestication is often partial, with class or geographical dimensions. Detroit is fully English, but its rich suburbs Belle Isle and Grosse Ile are fully French. Working-class Gibraltar (Jibber Alter) isn't even English!
In Kansas, the Swan Swamp River (Marais des Cygnes) is part French. The second and third words are French, but Marais rhymes with Sarah. La Cygne, the swan city on the swan swamp, is fully French.