reservoir

REZ-er-vwar /ˈrɛzəvwɑːr/
nounB2IELTSTOEFL
GeneralTechnical

A large natural or artificial lake used as a source of water supply.

Can also refer to a supply or stock of something abstract (e.g., a reservoir of knowledge).

The story behind the word. From the French 'réservoir,' based on 'réserver' (to reserve). It literally means a place where things are kept back for later use.

Word relationships

  • basin: A basin is a natural depression; a reservoir is specifically for storage.

Commonly confused with

  • cistern: A cistern is a small, often underground tank; a reservoir is a large lake-scale storage.

Word family

  • reserve (verb): To keep back or set aside.

Collocations

  • water reservoir
  • vast reservoir
  • underground reservoir

Example sentences

  • "The city's reservoir levels have dropped significantly due to the prolonged drought." Environmental Science
  • "The gallbladder acts as a reservoir for bile." Anatomy

Memory hook

A reservoir is where you 'reserve' water. Water storage lake.

When not to use

Don't use for a small tank or a swimming pool.

Fun facts

  • The largest artificial reservoir in the world by surface area is Lake Volta in Ghana.

Related words

aqueduct, conduit

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