Definition of weak sister
: a member of a group who needs aid; also : something weak and ineffective as compared with others in a group
Examples of weak sister in a sentence
The company is no longer a weak sister among auto producers.
First Known Use of weak sister
WEAK SISTER Defined for English Language Learners
Definition of weak sister for English Language Learners
: a member of a group that is weak or unsuccessful in comparison to others in the group
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