2. to bang (e.g. one's head); to knock; to hit; to beat (against, on); to batter
固いものを打ちつける音が、聞こえてきた。The sound of something hard being struck could be heard.
3. to throw (at a wall, on the floor, etc.); to fling (at)
そして彼は手に持っていたものを、地面に打ちつけた。Then he flung what he was holding to the ground.