The online Merriam-Webster dictionary has these definitions for refute:

I then wrote:

After your note, I felt compelled to check print dictionaries with evidence.

1) Dictionaries, esp. modern, are descriptive, not proscriptive. So, poor usage will be reported. That does not make it "technically correct," whatever you may mean by that.

2) The simple gloss you give doesn't show any change of usage, or show what level of speech is reflected. Is this a traditional use, found in good authors? Or is it some corrupt form? We don't know from that citation.

3) OED and Merriam-Webster's 2nd: neither knows the refute = deny usage. Refute traditionally means very strongly to disprove or overthrow by argument. Given its etymology and its past, "refute" entails presentation of compelling evidence.

4) OED supplement (the 4-vol published supplement) has a new meaning, #5 vb transitive: "Sometimes used erroneously to mean 'deny, repudiate'." The earliest use is 1964, where it says that its use on the BBC shocks strict users, i.e., it's known, but clearly as inferior. Perhaps post-war? Other citations are from '78, '79, '80 (about as late as OEDS would get). "Erroneously," it says, i.e., clearly used by people not thinking clearly about what they needed to say, and just wanting the stronger-sounding word, regardless of its meaning.

So, while "refute = deny" may have some currency, it is clearly substandard usage, to be avoided and corrected. Just because it may be "English" doesn't mean it's good English. There are good reasons why it's bad English.

To read the earlier E-Sylum article, see: VOCABULARY WORD: REFUTE (www.coinbooks.org/esylum_v12n25a13.html)