What does the word monitor mean?

Usage examples for monitor

  1. Each monitor of the firmament moving in its own place according to its power with the magnet of its own nature to do the things it was created to do, until its work should be finished; then it falls from its place when its course is run, and is no more. – The Secret of the Creation by Howard D. Pollyen
  2. She, too, like the Monitor, had had her fill of fighting for that day. – Terry's Trials and Triumphs by J. Macdonald Oxley