undoubtingly

comparative more undoubtingly · superlative most undoubtingly

1. Without doubting.

   Poor Mr. Orme! I am sorry he is not well. It is cruel in you, Lucy, at this time, to say (so undoubtingly) that his illness is owing to his love of me.

   1753, Samuel Richardson, The History of Sir Charles Grandison, London: Harrison & Co., published 1785, Volume 4, Letter 14, p. 525

   3 more examples

   1659, John Pearson, An Exposition of the Creed, London: J. Williams, 6th edition, 1692, Article VIII, p. 316, But were there nothing, which is already said, demonstrated, there is enough written in the Word of God to assure us of the Deity of the Holy Ghost, to make us undoubtingly believe that the Spirit of God is God.

   […] she relied so undoubtingly on Sir John’s description of the house, as to feel no curiosity to examine it herself till she entered it as her own.

   1811, [Jane Austen], chapter 5, in Sense and Sensibility […], volume (please specify |volume=I to III), London: […] C[harles] Roworth, […], and published by T[homas] Egerton, […], →OCLC

   There is a class of persons (happily not quite so numerous as formerly) who think it enough if a person assents undoubtingly to what they think true, though he has no knowledge whatever of the grounds of the opinion, and could not make a tenable defence of it against the most superficial objections.

   1859, John Stuart Mill, “[Dedication]”, in On Liberty, London: John W[illiam] Parker and Son, […], →OCLC, page 2