tooth fairy

American  

[tooth fair-ee] / ˈtuθ ˌfɛər i /

noun

1. a fairy credited with leaving a child money or a small gift in exchange for a baby tooth that has fallen out and been placed under the child's pillow at night.

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tooth fairy Idioms  

1. A mythical source of bounty, as in So who will finance this venture—the tooth fairy? This expression refers to the fairy credited with leaving money under a child's pillow in place of a baby tooth that has fallen out, a practice popular with American parents since the first half of the 1900s.

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Example Sentences

There’s even a tech opportunity for the tooth fairy.

From Barron's • Apr. 7, 2026

Yet when I express such views, I feel like I’m clinging to a belief in the tooth fairy, the Easter Bunny and Santa Claus.

From Salon • Aug. 10, 2025

That is the inevitable end of her sentence—and its astonishing realism has absolutely nothing to do with the tooth fairy.

From Slate • Jun. 4, 2025

The tooth fairy deposits money under a pillow and no one ever sees her — or him or them.

From Los Angeles Times • Dec. 22, 2024

We just have to pick up the tooth fairy and Superman and we’ll get right on it.

From "Lawn Boy" by Gary Paulsen