rigour

1. Severity or strictness. (countable, uncountable)
2. Harshness, as of climate. (countable, uncountable)
3. A feeling of cold with shivering accompanied by a rise in body temperature. (countable, uncountable)
4. Character of being unyielding or inflexible. (countable, uncountable)
5. Shrewd questioning. (countable, uncountable)
6. Higher level of difficulty. (countable, uncountable)

Plural rigours