I've heard of the term. My grandmother was Irish-Catholic, though later than the historical knownothingism movement you cited. How I should "ping" this escapes me though. The OP is apparently citing an article that purports to quote someone channeling the Virgin Mary, who is declaring she is going to crush "the serpent." If eating popcorn over that gives any insult to the teachings of Catholicism, I'm open to learning about my mistake.