What is the meaning of Rigor?

US spelling of rigour.

A feeling of cold with shivering accompanied by a rise in body temperature.

Ellipsis of rigor mortis.

rigour/rigor

precision, exactness

harshness

apocopic form of rigore

stiffness, rigidity

rigor, cold, harshness, severity

harshness; severity

stiffness; rigidity

rigour (higher level of difficulty)

rigour (severity or strictness)

rigidity; inflexibility

rigour

rigour

Source: wiktionary.org