"Faynits" or similar.

[Escutcheon]

Does anyone know the origin of the childrens saying "faynits" (?) and crossing your fingers when wanting a short break during a playground game?

[boxer]

Is this any help- 'It’s variously spelt, as fainites, faynits, or fains, all of which are a slight corruption, or a running-together, of fain I, or fain it. In fact, it’s often said as though it’s spelt “fain-its”. The word is school slang dating from at least the 1870s, but it was a dialect term earlier still. It’s a form of fend, which at one time had a meaning of “to forbid”. Another version current last century was fen, often said as ven.'

[phylkat]

Is that so boxer? we as kids used to say "Fainlites" .....
J