When an item is to be found in the world of ruin, the acquired abbrev will be followed with an R.
For example, the weapon "Striker" is found in the Veldt Caves, in a chest. Therefore, the abbreviation is VC(C,R). The R signifies the item is acquired in the world of ruin.
The information given here is only basic. For further information, check out the walkthrough or the shops list.