kenkäraja

Noun

 * 1) A worn-out shoe.

Noun

 * 1) In a facility where avoiding contamination is essential, such as a laboratory or a nuclear power plant, a boundary through which one is not allowed to go without covering/uncovering the shoes, depending on which way one is going.

Usage notes

 * In Nordic countries an English term "shoe boundary" is used of this concept, but it does not seem to be used in the English-speaking world.