Accuracy is a player statistics in Strife, used by its ranged weapons. It starts at 0 and maxes at 100. The lower the accuracy, the more player attacks tend to err wildly off course.
Accuracy is increased by UpgradeAccuracy items which are granted at various points during the game.
It can be set for custom actors with the Accuracy property, accessed from ACS with APROP_Accuracy, and used in DECORATE expressions.
The alternate HUD will show the player's current accuracy and stamina if hud_showstats is true.