I picked up 'The Official Dictionary of Poker' at a used bookstore. Comes from the Mike Caro University. My book is copyright 1999.
The NUTS are defined as;
the best posible hand at any particular point in a pot.
So, one can have the NUTS which can only be AA preflop according to that definition. The NUTS will change after the flop, the turn, and the river. The only time I can figure that the preflop nuts will remain the absolute nuts is with an AAx flop. If that x is a K and one of the Aces matches, then watch out, fireworks be happening here. One more of the royal family puts those absolute quad aces at posible risk. Granted the odds
are nearly imposibly improbable, but truthfully, I am more than willing to be on the loosing side of that showdown.
I can find no reference to suited cards being called the NUTS, however many old terms have evolved from thier original useage.