Purse strings is a draw string used to close a handbag, or is slang for having control over the money.(noun)
When the wife is in charge of the money in the family and gives her husband an allowance, this is an example of when the wife has the purse strings.
See purse strings in Webster's New World College Dictionary
See purse strings in American Heritage Dictionary 4
or purse·stringsplural noun
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