по дереву

on wood

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phrase Rare #45,464
on wood Depending on context, it can also mean working with wood or moving around on a tree. In «постучать по дереву», it means “knock on wood.”
RU: Он постучал по дереву.
EN: He knocked on the wood.

Работает по дереву.

It works off the tree.

— Leto (2018)

Постучи по дереву.

Knock on wood.

— Жизнь Адель (2013)