Rigor Mortis Is the Stiffness of Death
Rigor is strictness or severity. In medicine it names both a fit of shivering and the stiffening of a body after death.
Rigor is strictness or severity, and in medicine a sudden attack of shivering with fever. Latin *rigor* meant stiffness, from *rigere*, to be stiff — which explains *rigor mortis*, the stiffness of death, when muscles lock a few hours after death as their chemical fuel runs out. It passes within a day or two as tissues break down. The spelling *rigour* is British for the general sense, but *rigor mortis* keeps the Latin form everywhere.
- Strictness. *Academic rigour.*
- A fit of shivering. *A rigor and high fever.*
- Rigor mortis — stiffness after death. *Rigor mortis.*
- Rigid — stiff. *Rigid.*
- Latin — *rigere*, to be stiff. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun (US) | rigor | Rigor. |
| Noun (UK) | rigour | Rigour. |
| Adjective | rigorous | Rigorous. |
| Related | rigid | Rigid. |
| Latin | rigere | To be stiff. |
- The study lacks rigour.Strictness.
- Rigor mortis sets in within hours.Medicine.
- The patient had a rigor overnight.Shivering.
How rigor mortis works
- Muscles need ATP to release after contracting
- After death the supply stops and fibres stay locked
- Stiffness begins within two to six hours
- It peaks around twelve hours and then fades
- It passes as tissues begin to break down
Latin *rigor*, stiffness or hardness, from *rigere*, to be stiff or numb with cold.
What causes rigor mortis?
Muscles need a chemical fuel to release after contracting. When it stops being produced after death, the fibres stay locked until tissues break down.
Rigor or rigour?
Rigour is the British spelling for strictness; American English uses rigor. The medical rigor mortis keeps the Latin spelling everywhere.