'Legitimacy' definitions:

Definition of 'legitimacy'

(from WordNet)
noun
Lawfulness by virtue of being authorized or in accordance with law [ant: illegitimacy]
noun
Undisputed credibility [syn: authenticity, genuineness, legitimacy]

Definition of 'Legitimacy'

From: GCIDE
  • Legitimacy \Le*git"i*ma*cy\ (-[i^]*m[.a]*s[y^]), n. [See Legitimate, a.] The state, or quality, of being legitimate, or in conformity with law; hence, the condition of having been lawfully begotten, or born in wedlock. [1913 Webster]
  • The doctrine of Divine Right, which has now come back to us, like a thief from transportation, under the alias of Legitimacy. --Macaulay. [1913 Webster]

Synonyms of 'legitimacy'

From: Moby Thesaurus