Word Study
rhesus
CIDE DICTIONARY
rhesus, n. [L. Rhesus, a proper name, Gr. .].
A monkey; the bhunder. [1913 Webster]
OXFORD DICTIONARY
rhesus, n. (in full rhesus monkey) a small catarrhine monkey, Macaca mulatta, common in N. India.
Idiom
rhesus baby an infant with a haemolytic disorder caused by the incompatibility of its own rhesus-positive blood with its mother's rhesus-negative blood. rhesus factor an antigen occurring on the red blood cells of most humans and some other primates (as in the rhesus monkey, in which it was first observed). rhesus negative lacking the rhesus factor. rhesus positive having the rhesus factor.
Etymology
mod.L, arbitrary use of L Rhesus f. Gk Rhesos, mythical King of Thrace
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