weak sister

noun

, Informal.

1. a vacillating person; coward.
2. a part or element that undermines the whole of something; a weak link.

weak sister

noun

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

Word History and Origins

Origin of weak sister¹

First recorded in 1855–60

Example Sentences

Unsatisfactory in her home, the weak sister does not do much better in society.

From Project Gutenberg

She is the limit beyond which no one must go, under pain of such displeasure as the weak sister can show.

From Project Gutenberg

Fortunately for the world, the weak sister and her theories do not rule.

From Project Gutenberg

And later on, when I knew her, she was a weak sister whom I tried to help.

From Project Gutenberg

He waz rather a weak sister, and alwus rode sideways on a side-saddle.

From Project Gutenberg