It’s a patent absurdity on the face of it to hate people because they live round the corner and speak another vernacular, in the next house so to speak.
There are no more uses of "vernacular" in the book.
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At our several get-togethers since then it had given me great pleasure to help interpret Faulkner for Sophie, not only by way of explaining parts of the occult Mississippi vernacular but in showing her some of the right pathways as she penetrated the wonderful groves and canebrakes of his rhetoric.
William Styron -- Sophie’s Choice
I thought about him in that way, to borrow a phrase from the middle school vernacular.