Jump To:

• rhesus
  rhesus

  noun

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

  noun

  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

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

See Examples For:

rhesus Rhesus

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

For the study, a team of researchers from Germany and the USA trained two rhesus monkeys to explore an experimental room with two button-controlled food boxes.

From Science Daily ● Mar. 6, 2024

Chinese researchers have cloned the first rhesus monkey, a species which is widely used in medical research because its physiology is similar to humans.

From BBC ● Jan. 16, 2024

His voice was as loud as the scolding of a rhesus monkey high in the sundari trees.

From "Tiger Boy" by Mitali Perkins

Macaque species score even lower, ranging from 2.3% in Japanese macaques to just 1% in Rhesus macaques.

From Science Daily ● Jan. 22, 2026

Rhesus monkeys are found in the wild in Asia, with populations in Afghanistan through India, Thailand, Vietnam and China.

From BBC ● Jan. 16, 2024

The Rh blood group was first discovered in Rhesus monkeys.

From Textbooks ● Jun. 9, 2022

Rhesus macaques infected with SARS-CoV-2 could not be reinfected at just under one month following their initial infection, according to an unreviewed study4 by researchers at Peking Union Medical College in Beijing.

From Nature ● Apr. 17, 2020

They knew not, whispered not, Rhesus had ever come.

From The Rhesus of Euripedes by Euripedes