It is silly to believe that words do not change with the passage of time. Wine can refer to either unfermented wine or fermented wine. Just look up the word "wine" at dictionary.com.
Again, the word yayin comes from a root that means fermented.
Melchizedek provided yayin to Abraham.
Scripture should be used to prove Scripture whenever possible, not something in dictionary.com that was written thousands of years later.
Show me some verses in the book of Genesis where you think yayin is grape juice and not wine that contains alcohol.