In my opinion, the term 'veriest' is quite unusual and in current English would usually only be used in a very specific way, as an 'intensifier', such as: "nobody except my veriest friend knows my secret"

veriest : True; real; actual; veriest friend = true friend http://define.com/veriest

veriest means unforgettable. example: if you give a party to your friend and he didn't give party and left you then its veriest friend

I agree with Neal, it does sound unusual. Read it as meaning "most very". So the friend is not only very much a friend, but the best example ("+est") of being very much a friend.

i am a veriest panther :P