weak sister

American  

noun

Informal.

1. a vacillating person; coward.

2. a part or element that undermines the whole of something; a weak link.

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weak sister British  

noun

1. informal a person in a group who is regarded as weak or unreliable

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Etymology

Origin of weak sister

First recorded in 1855–60

Example Sentences

Fear is a very weak sister and, yes, they really should get rid of those brooding teenagers and maybe Travis too.

From New York Times • Apr. 18, 2016

Someone suggested that he could buy the down-at-the-heels New York Yankees, weak sister of the American League, for $450,000.

From Time Magazine Archive

Started two years ago to give the fast-growing News-Free Press a run for its money, the evening Times remained a weak sister.

From Time Magazine Archive

Circulationwise it has remained a weak sister in her hands, trailed among Manhattan's afternoon dailies only by Field's P.M.

From Time Magazine Archive

"But there might be some nicer gentleman just as wealthy, might there not?" suggested the weak sister.

From Lippincott's Magazine of Popular Literature and Science Volume 15, No. 86, February, 1875 by Various