attrition

noun

• 1the process of reducing something’s strength or effectiveness through sustained attack or pressure:the council is trying to wear down the opposition by attrition the squadron suffered severe attrition of its bombers
• chiefly North American & Australian/NZ the gradual reduction of a workforce by employees leaving and not being replaced rather than by redundancy: the company said that it will reduce its worldwide employment by about 10% through attrition
• wearing away by friction; abrasion:the skull shows attrition of the edges of the teeth

• 2(in scholastic theology) sorrow for sin, falling short of contrition.