shadow-box

noun

1. a shallow, rectangular frame fronted with a glass panel, used to show and at the same time protect items on display, as paintings, coins, or jewelry.

verb (intr)

1. boxing to practise blows and footwork against an imaginary opponent
2. to act or speak unconvincingly, without saying what one means, etche’s just shadow-boxing

n.protective display case, 1892, from shadow (n.) + box (n.1).