What does the word watershed mean?

Usage examples for watershed

  1. The Brothers therefore became satisfied of what they had long believed, that they had never been on the Lynd at all, or even on its watershed, and that what they were on was an independent stream. – The Overland Expedition of The Messrs. Jardine by Frank Jardine and Alexander Jardine
  2. After getting into camp I rode out south towards the watershed but found it further off than I anticipated from this camp. – McKinlay's Journal of Exploration in the Interior of Australia by John McKinlay
  3. It must be held back on the watershed of every source stream. – Our National Defense: The Patriotism of Peace by George Hebard Maxwell