credibly

In a credible manner; believably.

A suitor can credibly signal his love for a woman by offering her an expensive and extravagant gift.

He was in a position to commit to a credibly conservative monetary policy.

Used to report the speaker's assessment of the credibility of a reported statement

He [Mayor Koch] says he better understands the limits of government; less credibly, he says he has mellowed.

His deep-set eyes and expression of general despair lend him a look of utter dissolution—very credibly, he is dying from sexual desire.