DEFINITION of 'Weak Sister'
An element that undermines the entire system. Weak sister can either refer to a single individual or a specialized group considered to be the weak link in an integrated process.
BREAKING DOWN 'Weak Sister'
Usually referring to an undependable member of a group environment, the weak sister can also be a malfunctioning part of a team oriented task. For example, the slowest member in an assembly line or a slow marketing team which hinders the overall performance of operations is referred to as the weak sister.