Slightly off, as a picture frame

ASKEW

Think of how something might look if it were tilted just enough to seem uneven, like a painting that hasn’t been hung quite straight.

The clue describes something that isn’t quite straight or aligned, like a picture frame hanging crooked on the wall. "Askew" fits perfectly because it means tilted or awry, matching the idea of being "slightly off." There’s no hidden wordplay here—just a straightforward definition where the answer directly reflects the clue’s meaning.