reservoir

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A natural or artificial pond or lake used for the storage and regulation of water.
2. n. A receptacle or chamber for storing a fluid.
3. n. An underground accumulation of petroleum or natural gas.
4. n. Anatomy See cisterna.
5. n. A large or extra supply; a reserve: a reservoir of good will.
6. n. Medicine An organism or a population that directly or indirectly transmits a pathogen while being virtually immune to its effects.

Century Dictionary and Cyclopedia

1. n. A place where anything is kept in store: usually applied to a large receptacle for fluids or liquids, as gases or oils.
2. n. Specifically A place where water collects naturally or is stored for use when wanted, as to supply a fountain, a canal, or a city, or for any other purpose.
3. n. In anatomy, a receptacle. See receptaculum.
4. n. In botany:
5. n. One of the passages or cavities found in many plant-tissues, in which are secreted and stored resins, oils, mucilage, etc. More frequently called receptacle.
6. n. A seed or any organ of a plant in whieh. surplus assimilated matter (reserve material) is stored up for subsequent use.
7. To furnish with a reservoir; also, to collect and store in a reservoir.
8. n. In organ-building, same as storage-bellows. See bellows, 3, and organ, 6.

Wiktionary

1. n. A place where anything is kept in store; especially, a place where water is collected and kept for use when wanted, as to supply a fountain, a canal, or a city by means of aqueducts.
2. n. A small intercellular space, often containing resin, essential oil, or some other secreted matter.
3. n. A supply or source of something.

GNU Webster's 1913

1. n. A place where anything is kept in store; especially, a place where water is collected and kept for use when wanted, as to supply a fountain, a canal, or a city by means of aqueducts, or to drive a mill wheel, or the like.
2. n. (Bot.) A small intercellular space, often containing resin, essential oil, or some other secreted matter.
3. n. (Med.) a large quantity of infectious microorganisms resident in animals other than man, potentially capable of being transmitted to humans.
4. n. (Med.) a large quantity of infectious microorganisms or parasites resident in animals other than man, potentially capable of being transmitted to humans; especially, such organisms in animals where they do little or no harm to the host.
5. n. a large supply or stock of anything which may be rapidly put to use; a reserve.

WordNet 3.0

1. n. lake used to store water for community use
2. n. tank used for collecting and storing a liquid (as water or oil)
3. n. a large or extra supply of something
4. n. anything (a person or animal or plant or substance) in which an infectious agent normally lives and multiplies