reservoir

noun
res·​er·​voir | \ ˈre-zə-ˌvwär How to pronounce reservoir (audio) , -zər- How to pronounce reservoir (audio) , -ˌvwȯr How to pronounce reservoir (audio) also -ˌvȯi \

Definition of reservoir

1 : a place where something is kept in store: such 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 : an extra supply : reserve
3a : a host organism in which an infectious agent (such as a bacterium or virus) that is pathogenic for some other species lives and multiplies typically without damaging the host

Note: A reservoir serves as a source from which transmission of infection and outbreaks of disease can occur.

It is the white-footed mouse that serves as a natural reservoir host for the spirochete B. [Borrelia] burgdorferi. These mice carry the spirochete without any apparent harm to themselves, and it is through feeding on infected mice that the immature stages of the tick acquire the spirochete.— Suzanne Clothier et al.
also : a nonliving thing (such as soil or water) in which an infectious agent lives and multiplies and which serves as a source of infection similar to a host organism
b : a part of the body that harbors an infectious agent and serves as a source of reinfection or infection transmission … vulvar or rectal reservoirs, which might increase risk for BV [bacterial vaginosis] recurrence.— Lisa E. Manhart et al. — compare carrier sense 5a, vector entry 1 sense 2a

Examples of reservoir in a Sentence

The pen has a large ink reservoir. Colleges and universities provide reservoirs of talent for job recruiters. She found the reservoirs of energy she needed to finish the job.
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Recent Examples on the Web The waters held back by the main dam created a reservoir that flooded 260 square miles of lowlands and forests, and displaced more than 20,000 people. Matt Reynolds, Wired, 16 Nov. 2021 Soils were so dry and temperatures so warm that the water instead was soaked up or evaporated, and reservoir water storage fell to shocking levels. NBC News, 10 Nov. 2021 This beautiful kit features two adjustable LED lights with an automatic on and off switch and a 68 fluid-ounce reservoir that holds enough water for your plants for four weeks. Jennifer Aldrich, Better Homes & Gardens, 5 Nov. 2021 Utah officials make plans to build a reservoir that would hold Bear River water to feed urban growth along the Wasatch Front. The Salt Lake Tribune, 4 Nov. 2021 But, unlike in the rest of the American West, the extreme water scarcity plaguing this tiny corner of far Northern California was not the result of dwindling snowpack or plummeting reservoir levels. Justin Ray, Los Angeles Times, 28 Oct. 2021 The purified sewage might be pumped directly into the city’s water supply, instead of being placed first into a city reservoir — Lake Miramar is being used for phase one. David Garrick, San Diego Union-Tribune, 28 Oct. 2021 How do reservoir levels look across Northern California? Gwendolyn Wu, San Francisco Chronicle, 26 Oct. 2021 Water levels at Lake Oroville, California’s second largest reservoir, increased by 26 feet. Washington Post, 28 Oct. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reservoir.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of reservoir

1690, in the meaning defined at sense 1

History and Etymology for reservoir

French réservoir, from Middle French, from reserver

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Time Traveler for reservoir

Time Traveler

The first known use of reservoir was in 1690

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Dictionary Entries Near reservoir

reservist

reservoir

reservoir rock

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Statistics for reservoir

Last Updated

26 Nov 2021

Cite this Entry

“Reservoir.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reservoir. Accessed 1 Dec. 2021.

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More Definitions for reservoir

reservoir

noun

English Language Learners 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

reservoir

noun
res·​er·​voir | \ ˈre-zər-ˌvwär How to pronounce reservoir (audio) \

Kids Definition of reservoir

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

reservoir

noun
res·​er·​voir | \ ˈrez-ə(r)v-ˌwär How to pronounce reservoir (audio) , -ə(r)v-ˌ(w)ȯr How to pronounce reservoir (audio) \

Medical Definition of reservoir

1 : a space (as an enlargement of a vessel or the cavity of a glandular acinus) in which a body fluid is stored
2a : a host organism in which an infectious agent (as a bacterium or virus) that is pathogenic for some other species lives and multiplies typically without damaging the host

Note: A reservoir serves as a source from which transmission of infection and outbreaks of disease can occur.

Wild rodents also constitute a reservoir of hantaviruses. The viruses are shed in urine, droppings, and saliva, and humans are mainly infected aerogenically by inhaling aerosols containing the virus.— Hilde Kruse et al., Emerging Infectious Diseases
also : a nonliving thing (as soil or water) in which an infectious agent lives and multiplies and which serves as a source of infection similar to a host organism
b : a part of the body that harbors an infectious agent and serves as a source of reinfection or infection transmission … vulvar or rectal reservoirs, which might increase risk for BV [bacterial vaginosis] recurrence.— Lisa E. Manhart et al., Infectious Diseases in Obstetrics and Gynecology carrier sense 1a, vector entry 1 sense 2

More from Merriam-Webster on reservoir

Nglish: Translation of reservoir for Spanish Speakers

Britannica English: Translation of reservoir for Arabic Speakers

Britannica.com: Encyclopedia article about reservoir

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