If you describe something as glancing, that means it's quick and angled, like the glancing blow you give a fellow actor with your stunt sword.
An onstage sword fight, especially one that's played for comedy, is full of glancing hits. These are aimed to bounce, or glance, off their objects. The oldest use of glancing is "strike obliquely, without full impact," from an Old French word meaning "to make slippery." Another way to use this adjective is to mean "indirect," like the glancing references you make to dogs in every conversation with your parents, hoping they'll get the hint and adopt a puppy.