Definition from Wiktionary, the free dictionary
- Serving to confirm something.
- 1850, Charles Dickens, David Copperfield, Chapter 41, 
- I replied, as I usually did whenever I had a chance, that nobody had ever loved anybody else as I loved Dora. Traddles came to my assistance with a confirmatory murmur.
- 1924, Herman Melville, Billy Budd, London: Constable & Co., Chapter 16, 
- "Do you come to me, Master-at-arms, with so foggy a tale? As to Budd, cite me an act or spoken word of his confirmatory of what you in general charge against him. […] "
- 1986, Mark S. Gold and A.L.C. Pottash, Diagnostic and Laboratory Testing in Psychiatry, New York and London: Plenum Medical Book Company, Chapter 3, p. 43, 
- The main indication for performing the DST is for the confirmation of suspected major depression. A positive test is excellent confirmatory evidence of the diagnosis.
- 1850, Charles Dickens, David Copperfield, Chapter 41,