DictionarycootieImaginary contamination
noun

cootie

KOO-tee/ˈkuːti/

An imaginary germ or source of contamination in children's play.

The children pretend that a cootie can pass through a fingertip touch.

Two panels show children playfully avoiding and returning a touch with crossed fingers.
Etymology

From a real body louse, cootie became a child’s imaginary source of contamination.

More examples

  • She crossed her fingers to ward off cooties.
  • The playground game involved chasing away imaginary cooties.

Forms

cootie · cooties

Similar words

germ
Usually names a real microscopic organism.
contamination
Is the broader idea of becoming unclean or affected.