Very early in her married life he had decided — though perhaps it was only that he knew her more intimately than he knew most people — that she had without exception the most stupid, vulgar, empty mind that he had ever encountered.
There are no more uses of "vulgarity" in the book.
Show samples from other sources
Her vulgarity was a turnoff.
As if I’d ever given her grounds to believe I’d stoop to such vulgarity!