@Fuko
INT is magic. Yes, it means intelligence. INT relates to how much your mana pool is and how fast will your mana recover. And it's tied to wizards who learns and uses arcane magic. Not just magic but also in basic things such as reading, writing, etc.
STR = Strength
AGI = Agility
INT = Intelligence
DEX = Dexterity
VIT = Vitality
LUK = Luck
ATK = Attack
DEF = Defense
MATK = Magical Attack
MADEF = Magical Defense
CRIT = Critical Damage
the first 4 are architypes, while the rest are stats. The said first 4 are also stats. If you have high STR and VIT for tanks, INT for DPS or healing, AGI and DEX for attack speed and/or evasion, so on and so forth.
Disclaimer: My interpretation of these stats is outside of DnD