with certainty (adverb) positively: absolutely, definitely
Sinonime: amen, assuredly, categorically,
certainly, doubtless, doubtlessly,
easily,
emphatically,
firmly, flat out,
flat*, for a fact,
indubitably, no catch, no holds barred, no ifs ands or buts, no kicker, no strings attached, on the money, on the nose, really truly, right on,
sure,
surely, the ticket, to a tee, undeniably,
undoubtedly, unequivocally, unmistakably, unquestionably, with certainty, without qualification
Antonime: doubtfully, questionably