Pinky swear

To pinky swear, or to make a pinky promise, is the entwining of the little fingers ("pinkies") of two people to signify that a promise has been made.

In the United States, the pinky swear has existed since at least 1860, when Dictionary of Americanisms listed the following accompanying promise:

Pinky swearing presumably started in Japan, where it is called yubikiri (指切り^?, "finger cut-off") and often additionally confirmed with the vow "Finger cut-off, ten thousand fist-punchings, whoever lies has to swallow thousand needles." (「指切りげんまんうそついたら針千本のます」, "Yubikiri genman uso tsuitara hari senbon nomasu"^?). The gesture may be connected to the Japanese belief that soulmates are connected by a red string of fate attached to each of their pinkies.

In Japan, the pinky swear originally indicated that the person who breaks the promise must cut off their pinky finger. In modern times, pinky swearing is a more informal way of sealing a promise. It is most common among school-age children and close friends. The pinky swear signifies a promise that can never be broken.

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