cast a pall upon (something)

To cause something to become sad or somber; to darken or tarnish something. A dated variant of "cast a pall on something." The headmaster's sudden death really cast a pall upon the school's graduation ceremony. The economic crash was devastating, casting a pall upon the entire world for years. A: "Applications are way down." B: "It's official, then—the coaching scandal has cast a pall upon the whole university."

cast a pall upon, to

To spread gloom. A pall was a cloth or cloak thrown over a coffin. By the eighteenth century the term had been transferred to spiritual darkness (“By this dark Pall thrown o’er the silent world,” Edward Young, Night Thoughts, 1742).