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noun res·er·voir \ˈre-zə-ˌvwär, -zər-, -ˌvwȯr also -ˌvȯi\

Simple Definition of reservoir

  • : a usually artificial lake that is used to store a large supply of water for use in people's homes, in businesses, etc.

  • : a place (such as a part of a machine) where a liquid is stored

  • : an extra supply of something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of reservoir

  1. 1 :  a place where something is kept in store: as a :  an artificial lake where water is collected and kept in quantity for use b :  a part of an apparatus in which a liquid is held c :  supply, store <a large reservoir of educated people>

  2. 2 :  an extra supply :  reserve

  3. 3 :  an organism in which a parasite that is pathogenic for some other species lives and multiplies usually without damaging its host

Examples of reservoir in a sentence

  1. The pen has a large ink reservoir.

  2. Colleges and universities provide reservoirs of talent for job recruiters.

  3. She found the reservoirs of energy she needed to finish the job.

Origin and Etymology of reservoir

French réservoir, from Middle French, from reserver

First Known Use: 1690

Rhymes with reservoir

abattoir, acinar, air guitar, Aligarh, aide-mémoire, arctic char, au revoir, avatar, blazing star, bolivar, Bolívar, brittle star, bumper car, cabin car, cable car, café noir, Castlebar, cinnabar, coffee bar, color bar, command car, commissar, coplanar, Côte d'Ivoire, cultivar, deodar, dining car, double bar, double star, error bar, escolar, escritoire, evening star, exemplar, falling star, feather star, funny car, giant star, handlebar, insofar, isobar, Issachar, jacamar, jaguar, jaunting car, Kandahar, kilobar, Krasnodar, mason jar, megabar, megastar, millibar, minibar, minicar, Miramar, montagnard, morning star, motorcar, Mudejar, muscle car, Myanmar, neutron star, objet d'art, open bar, parlor car, pinot noir, Qiqihar, registrar, rent-a-car, repertoire, ricercar, rising star, salad bar, Salazar, samovar, scimitar, seminar, shooting star, Silver Star, simular, sleeping car, steak tartare, steel guitar, subahdar, superstar, tiki bar, torsion bar, touring car, tutelar, turbocar, Valdemar, VCR, Veadar, wrecking bar, wunderbar, X-ray star, Yourcenar, zamindar, Zanzibar

RESERVOIR Defined for Kids


noun res·er·voir \ˈre-zər-ˌvwär\

Definition of reservoir for Students

  1. :  a place where something (as water) is kept in store for future use

Medical Dictionary


play play play
noun res·er·voir \ˈrez-ə(r)v-ˌwär, -ə(r)v-ˌ(w)ȯr\

Medical Definition of reservoir

  1. 1:  a space (as an enlargement of a vessel or the cavity of a glandular acinus) in which a body fluid is stored

  2. 2:  an organism in which a parasite that is pathogenic for some other species lives and multiplies without damaging its host; also :  a noneconomic organism within which a pathogen of economic or medical importance flourishes without regard to its pathogenicity for the reservoir <rats are reservoirs of plague>—compare carrier 1a

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