Ball and Chain
Believed to have originated in Britain, this term has come to mean 'wife'. Originating from the presumption that a man's wife has held him down thus, keeping him from doing the things he really wanted to do in life.

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Email: The ball and chain referred to a device used to ground hitch a buggy horse where there was no hitching post available. The driver would set the weight on the ground and affix the end of the short chain to the bridle. The weight was sufficient to make the horse believe it was a solid post. A similar device was employed to slow a hunting dog that ranged too far. The drag would slow the animal sufficiently to avoid flushing game out of gun range.

(来源：英语麦当劳－英语快餐EnglishCN.com)