Statistics (shortened to Stats) are numerical attributes that affect a character's performance in battle.
Short for Level, LV represents a characters cumulative growth and power. In short, the higher their level, the more powerful. With each level, the character's stats become higher, improving their performance in battle. The degree to which their individual stats increase vary depending on the character. Some characters will have large increases to a few stats while minimal increases to others. This is referred to as their Stat Growth.
Short for Experience Points, EP represents a character's progress toward gaining a level. It is earned through defeating enemies in battles. When a character gains 1,000 EP they gain a level. However as a character's LV increases they'll earn progressively fewer EP from battles with the same opponents. At that point, the player should progress to a new area to fight against stronger enemies in order to continue leveling up.
Also known as Health or Health Points, HP represents a character's life force. This number can be reduced by enemy attacks and restored with healing items and specials. When it reaches zero that character is considered KOed. At that point they can be revived with items or specials. KOed characters will not receive EP from battle. However if Ari is KOed, it's Game Over and the player must restart from their last save.
Short for Labor Points, LP is a number representative of the amount of Specials or abilities that can be used. Each special has a certain "cost". Some require HP, but the majority require LP in order to be used.
Unlike HP, party members do not have their own distinct LP. Instead it is pooled and collectively used by the entire party. This means that once it is depleted, no one in the party will be able to use Specials that require LP.
In other games, this is sometimes referred to as Magic Power or MP.
Shortened to Atk in-game, Attack is a characters strength and directly affects their damage output in battle, the higher their Attack, the higher the damage. Weapons provide bonuses to this stat, so getting stronger weapons will improve it.
Shortened to Dfns, Dfnce, also known as Def, Defense is a character's defensive capability and directly affects the damage they receive in battle, the higher their Defense, the lower the damage. Defensive equipment provides bonuses to this stat, so using stronger defensive equipment will reduce the damage a character sustains in battle.
Agility also called Agi, is a character's speed in battle and directly affects how quickly their action bar fills. When full, that character is able to act, the higher the agility, the more quickly and more frequently that character is able to act. Some guard equipment can provide boosts to this stat.
Although it's not visible in the menu, Evasion, also known as Eva is a hidden stat that affects the frequency that enemies will miss when using physical attacks. Some equipment provides unlisted bonuses to Evasion, while some guard equipment alludes to it directly without providing specific stats.
Similar to Evasion, Magical Evasion, occasionally shortened to mEva, is another hidden stat that is not visible in the menu. Magical Evasion affects the frequency that enemies will miss when using magical attacks. Some equipment provides unlisted bonuses to Evasion, while some guard equipment alludes to it directly without providing specific stats.