bloodstream

noun

blood·​stream ˈbləd-ˌstrēm How to pronounce bloodstream (audio)
1
: the flowing blood in a circulatory system
2
: a mainstream of power or vitality
… introduce into the economic bloodstream a large amount of money …—Harper's

Examples of bloodstream in a Sentence

The drug is now entering the bloodstream.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The fungus, which can spread through skin-to-skin contact, poses a particular risk to already hospitalized patients and can lead to serious bloodstream infections. — Zachary Bynum, CBS News, 9 Aug. 2026 Some people injected the peptides into muscle instead of the arm or belly fat, which could alter how quickly the drugs reach the bloodstream. — C. Michael White, The Conversation, 7 Aug. 2026 They have also been found in the bloodstreams of 98% of people tested, as well as in wildlife, fish, water — including rivers, lakes and nearshore waters — and soil. — Susanne Rust follow, Los Angeles Times, 6 Aug. 2026 In people with weakened immune systems, the infection could spread to the bloodstream and be life-threatening. — Dominique Mosbergen, Time, 5 Aug. 2026 See All Example Sentences for bloodstream

Word History

First Known Use

13th century, in the meaning defined at sense 1

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

Rhymes for bloodstream

See All Rhymes for bloodstream

Browse Nearby Words

bloodstone
bloodstream
bloodsucker
See all Nearby Words

Cite this Entry

“Bloodstream.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bloodstream. Accessed 15 Aug. 2026.

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Kids Definition

bloodstream

noun
blood·​stream -ˌstrēm How to pronounce bloodstream (audio)
: the flowing blood in a living thing with a circulatory system

Medical Definition

bloodstream

noun
blood·​stream -ˌstrēm How to pronounce bloodstream (audio)
: the flowing blood in a circulatory system

More from Merriam-Webster on bloodstream

Nglish: Translation of bloodstream for Spanish Speakers

Last Updated: - Updated example sentences
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