Vapid

INANE

Think of a word that describes something so lacking in sense or substance that it might make you roll your eyes—like a joke that falls completely flat.

"Vapid" is a straightforward synonym clue pointing to "INANE," since both words describe something lacking depth or intelligence. The clue doesn’t rely on wordplay—it’s a direct definition where "vapid" and "INANE" share nearly identical meanings. If you think of "INANE" as a slightly more formal way to say "silly" or "empty-headed," the connection becomes clear. Solvers familiar with either word would recognize the match right away.