blood·​stream | \ ˈbləd-ˌstrēm How to pronounce bloodstream (audio) \

Definition of bloodstream

1 : the flowing blood in a circulatory system
2 : a mainstream of power or vitality introduce into the economic bloodstream a large amount of moneyHarper's

Examples of bloodstream in a Sentence

The drug is now entering the bloodstream.
Recent Examples on the Web Interferon also beckons cells such as macrophages in the bloodstream that can engulf virus particles. Mark Fischetti, Scientific American, "Support Science Journalism," 23 June 2020 Hydrocephalus is caused by an imbalance between how much cerebrospinal fluid is produced and how much is absorbed into the bloodstream., "The week in business," 13 June 2020 The presence of antibodies in the bloodstream indicate that someone already had the virus and recovered. Bob Sandrick, cleveland, "Broadview Heights healthcare firm provides COVID-19 antibody tests on City Hall campus," 9 June 2020 The fluid prevents the lungs from filling with enough oxygen, so less reaches the bloodstream, causing organs to fail. USA Today, "Can vitamin D help with symptoms of COVID-19? Possibly, it's key to helping your immune system function," 9 June 2020 While immune cells in the bloodstream and microglia in the brain both have cellular sensors to detect disease and injury, microglia can also detect neurons firing electrical impulses. Quanta Magazine, "Spreading the Word on a Possible Alzheimer’s Treatment," 27 May 2020 In Patterson's case, nine different phages were used in various cocktails injected into his bloodstream multiple times a day over 18 weeks. Claudia Wallis, Scientific American, "The Virtuous Side of Viruses," 26 May 2020 Chemotherapy delivers cancer killing drugs to the bloodstream, but these drugs can only reach as far as the blood vessels reach, and most of the tumor’s blood vessels do not get to the center of the tumor. New York Times, "A New Cancer Treatment That Is Faster, More Efficient and Less Risky Is Coming: Bacteria Bombs," 7 May 2020 Nor do the animations show how the light could reach other parts of the body evidently attacked by the virus, including the kidneys, central nervous system and the bloodstream. Los Angeles Times, "Column: How Cedars-Sinai got sucked into the battle over Trump’s claim of a COVID-19 treatment," 1 May 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'bloodstream.' 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 bloodstream

13th century, in the meaning defined at sense 1

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Time Traveler for bloodstream

Time Traveler

The first known use of bloodstream was in the 13th century

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Statistics for bloodstream

Last Updated

29 Jun 2020

Cite this Entry

“Bloodstream.” Dictionary, Merriam-Webster, Accessed 10 Jul. 2020.

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More Definitions for bloodstream


How to pronounce bloodstream (audio)

English Language Learners Definition of bloodstream

: the flow of blood that moves through the heart and body


blood·​stream | \ ˈbləd-ˌstrēm How to pronounce bloodstream (audio) \

Kids Definition of bloodstream

: the circulating blood in the body


blood·​stream | \ -ˌstrēm How to pronounce bloodstream (audio) \

Medical Definition of bloodstream

: the flowing blood in a circulatory system

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Rhyming Dictionary: Words that rhyme with bloodstream

Spanish Central: Translation of bloodstream

Nglish: Translation of bloodstream for Spanish Speakers

Britannica English: Translation of bloodstream for Arabic Speakers

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