Rh-negative

adjective

Rh-neg·​a·​tive ˌär-ˌāch-ˈne-gə-tiv How to pronounce Rh-negative (audio)
: lacking Rh factor in the red blood cells

Word History

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of Rh-negative was in 1945

Rhymes for Rh-negative

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Browse Nearby Words

rhm
Rh-negative
rho
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Cite this Entry

“Rh-negative.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Rh-negative. Accessed 11 Jul. 2026.

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Kids Definition

Rh-negative

adjective
ˌär-ˌāch-
: lacking Rh factor on the red blood cells

Medical Definition

Rh-negative

adjective
Rh-neg·​a·​tive ˌär-ˌāch-ˈneg-ət-iv How to pronounce Rh-negative (audio)
: lacking Rh factor in the red blood cells
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