have it on the highest authority
formalto have been told something by someone who knows the truth:
I have it on the highest authority that they are getting a divorce.
Thesaurus: synonyms and related words
Certainty
- (as) clear as day idiom
- (as) sure as eggs is eggs idiom
- and that's flat! idiom
- assured
- assuredly
- bet
- consider it done idiom
- cut and dried
- decided
- decidedly
- definite
- doubt
- indeed
- natch
- pronounced
- proof positive
- seal
- set/put the seal on sth idiom
- shadow
- signed and sealed idiom
See more results »