Mirepoix (cuisine)
Similar flavour bases include the Italian "soffritto", the Spanish "sofrito", "refogado/sufrito" (braised onions, garlic and tomato) from Portuguese-speaking nations, the German "suppengrün" (leeks, carrots and celeriac), the Polish "włoszczyzna" (leeks, carrots, celery root and parsley root), the US Cajun / Creole holy trinity (onions, celery and bell peppers), and possibly the French "duxelles" (mushrooms and often onion or shallot and herbs, reduced to a paste).
Troilism
One examination of the word may indicate a root in the French word "trois" (three). A similar French term, "triolisme", exists in French—the shift between the third and fourth letter is perhaps a mistake. On the other hand, "ménage à trois" (household of three) was coined in the late 19th century. Although all those terms involve three people, "ménage à trois" implies a romantic link between all three, which is quite different from troilistic scenarios. In French, a "plan à trois", vulgar form and synonym of "triolisme", corresponds more closely to a troilistic scenario; a "threesome".