rhesus

American  

[ree-suhs] / ˈri səs /

noun

1. a macaque, Macaca mulatta, of India, used in experimental medicine.

---

Rhesus British  

/ ˈriːsəs /

noun

1. Greek myth a king of Thrace, who arrived in the tenth year of the Trojan War to aid Troy. Odysseus and Diomedes stole his horses because an oracle had said that if these horses drank from the River Xanthus, Troy would not fall

---

Other Word Forms

• rhesian adjective

Etymology

Origin of rhesus

1830–40; < New Latin, arbitrary use of Latin Rhēsus name of a Thracian king allied with Troy < Greek Rhêsos

Example Sentences

On a tiny island called Cayo Santiago off the coast of Puerto Rico exists a colony of about 1,800 rhesus macaques.

From Salon • Mar. 16, 2025

The rhesus macaque fugitives busted out of Alpha Genesis, a company that breeds primates for medical testing and research, and are on the loose in a part of the state known as the Lowcountry.

From BBC • Nov. 7, 2024

They also isolated two antibodies from rhesus macaques -- a species of monkey with immune systems like humans' -- who previously had received a vaccine regimen designed to generate fusion peptide-directed antibodies.

From Science Daily • Jan. 17, 2024

They discovered that in failed rhesus attempts, the placentas, which provide oxygen and nutrients to the growing foetus, were not reprogrammed properly by the cloning process and so did not develop normally.

From BBC • Jan. 16, 2024

Neel strained to hear the sound of a soft mew of a cub, but the chatter of the rhesus monkeys and Headmaster’s loud panting made it impossible to hear anything else.

From "Tiger Boy" by Mitali Perkins