have something on good authority

have something on good authority (third-person singular simple present has something on good authority, present participle having something on good authority, simple past and past participle had something on good authority)

1. To know from a reliable source (that).

   Synonym: have it on excellent authority

   have it on good authority that …

• straight from the horse's mouth
• know for a fact
• from good hands

• “have something on good authority”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.
• “have something on good authority”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.
• “have something on good authority”, in Cambridge English Dictionary, Cambridge, Cambridgeshire: Cambridge University Press, 1999–present.
• “I have it on good authority” in Longman Dictionary of Contemporary English, Longman.
• “I have it on good authority that” (US) / “I have it on good authority that” (UK) in Macmillan English Dictionary.