sinusoid

noun

1
2
[New Latin sinus] : a minute endothelium-lined space or passage for blood in the tissues of an organ (such as the liver)

Word History

Etymology

Medieval Latin sinus sine

First Known Use

1823, in the meaning defined at sense 1

Time Traveler
The first known use of sinusoid was in 1823

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Cite this Entry

“Sinusoid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sinusoid. Accessed 7 Jul. 2026.

Medical Definition

: a minute endothelium-lined space or passage for blood in the tissues of an organ (as the liver)

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