Antonyms of adv untruthfully

1 sense of untruthfully

Sense 1
mendaciously, untruthfully -- (in a mendacious and untruthful manner; "I told him, quite untruthfully, that I had just returned from leave")
       Antonym of truthfully (Sense 1)
      => truthfully -- (with truth; "I told him truthfully that I had just returned from my vacation"; "he answered the question as truthfully as he could")

Synonyms of adv untruthfully

1 sense of untruthfully

Sense 1
mendaciously, untruthfully -- (in a mendacious and untruthful manner; "I told him, quite untruthfully, that I had just returned from leave")