Waaay back when I used to write fantasy for fun, I had a dragon in one of my stories named Barrow, who was a steel blue dragon with violet accents and webbing under his wings. While on all fours, Barrow stood about three times as tall as a human and had powerful claws to help him keep traction on ice, as well as an incredible tail to crush it with. He could be called upon in battle to assist, but only by those who were well in tune with the cold element, and would appear hostile towards anyone else unlucky enough to come across him (which in itself was very unlikely). Barrow was designed to be very territorial over his "invoker", and a symbol of the raw power of frost. He was natural enemies with Velvette, the flame serpent.
In short, I would name the Frostwyrm "Barrow".