[n] heavy pin having a head at one end and the other end being hammered flat after being passed through holes in the pieces that are fastened together
[n] ornament consisting of a circular rounded protuberance (as on a vault or shield or belt)
[v] focus one's attention on something; "Please focus on your studies and not on your hobbies"
[v] hold (someone's attention); "The discovery of the skull riveted the paleontologists"
[v] fasten with a rivet or rivets