reservoir

/ˈrɛzərvwɑr/
noun
  1. A natural or artificial lake where water is stored for use.
    • After the heavy rains, the reservoir reached its highest level in years.
    • The city gets its drinking water from a large reservoir in the mountains.
    • They went fishing at the reservoir behind the dam.
  2. A large supply or store of something (such as knowledge, energy, or resources).
    • She has a deep reservoir of patience when teaching young children.
    • His years of experience gave him a rich reservoir of stories to tell.
    • The country's reservoir of oil will last for decades.
  3. A part of a machine or device that holds a liquid or gas.
    • Check the windshield washer fluid reservoir before a long trip.
    • The humidifier has a removable water reservoir for easy cleaning.
    • The printer's ink reservoir needs to be refilled.