Rh-positive

adjective

Rh-pos·​i·​tive ˌär-ˌāch-ˈpä-zə-tiv How to pronounce Rh-positive (audio)
-ˈpäz-tiv
: containing Rh factor in the red blood cells

Word History

First Known Use

1941, in the meaning defined above

Time Traveler
The first known use of Rh-positive was in 1941

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Cite this Entry

“Rh-positive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Rh-positive. Accessed 3 Feb. 2026.

Kids Definition

Rh-positive

adjective
Rh-pos·​i·​tive
ˌär-ˌāch-ˈpäz-ət-iv
-ˈpäz-tiv
: having Rh factor on the red blood cells

Medical Definition

Rh-positive

adjective
: containing Rh factor in the red blood cells
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