DEF

Defence.

A term usually only used in role playing games (RPGs) and first person shooters (FPSs), DEF is a mathematical figure that is reached by combining a player's natural defence with that of their armour and any status effects that are upon them.

DEF is often also affected by the condition the armour is in; in some games armour also has hit points (HP), which is lowered when attacked, which means that the armour must be periodically repaired for the utmost effectiveness.