Definitions

1. noun

A plant of the genus Ricinus, especially the castor oil plant (Ricinus communis), which has seeds containing a toxic and highly allergenic oil.

“The ricinus plant is native to Africa and Asia, but it has been naturalized in many parts of the world.”

2. noun

In anatomy, the ricinus is a sheath of connective tissue that surrounds the tendon of a muscle, especially the flexor tendons of the fingers and toes.

“The ricinus sheath around the tendon helps to reduce friction and prevent injury.”