noun, noun which may take the genitive case particle 'no'
legitimacy; validity; justifiability
Refers to the quality of being legally, morally, or logically justified. Used in formal, legal, and everyday contexts to question or assert the rightness of an action, claim, or decision.
その政策の正当性が問われている。
The legitimacy of that policy is being questioned.
彼の主張
His claim lacks validity.
正当性のある理由を説明してください。
Please explain a justifiable reason.
妥当性 emphasizes appropriateness or suitability for a given situation, whereas 正当性 stresses inherent rightness or justification.
Compound of 正当 (せいとう, 'just, proper') + 性 (せい, '-ness, -ity'), forming an abstract noun meaning 'justness' or 'legitimacy'.