[David]

Originally Posted by Jim McDougall

I always wondered what in the world 'Mons Meg' meant, though clearly the Mons referred to the city in Flanders where it was from. According to what I could find in OED, the term 'meg' referred loosely to any huge ordnance, and or to the loud noise or report. In one reference around 1700, it was used describing loud noise of ringing bells and the discharge of 'roaring megs'.

Hey Jim, in the Wiki entry this info is sited to Agnes MacKenzie in the book Scottish Paegent.
"The gun is never called "Mons Meg" in any contemporary references until the 17th century. The "Meg" may either be a reference to Margaret of Denmark, Queen of James III of Scotland, or simply an alliteration, while Mons was one of the locations where the cannon was originally tested. McKenzie records that this class of artillery was known as a murderer and Mons Meg was certainly described as such."