Definitions

1. noun

A genus of Old World monkeys, especially Rhesus macaque.

“The rhesus macaque is a common primate found in Asia.”

2. adjective

Relating to or denoting the Rhesus macaque or the rhesus factor in the blood.

“The rhesus-positive blood type is relatively common.”

3. proper noun

A river in northern India, forming part of the border with Nepal.

“The Rhesus River flows through the Himalayas.”