Solution

STRICTNESS

3 clues

Firmness

Word class: Common noun
Nature of clue: Synonym
Difficulty: Easy

Other solutions to Firmness

Rigidity

Word class: Common noun
Nature of clue: Synonym
Difficulty: Easy

Other solutions to Rigidity

Severity

Word class: Common noun
Nature of clue: Synonym
Difficulty: Easy

Other solutions to Severity

Words are categorized by artificial intelligence: there can be mistakes.