osłonka v angličtině:

If a door doesn't fit the casing, we must plane it carefully until it does.

For safety purposes, remove the plastic casing before use.

In the darkness he loosened his sheath knife.

Iaido is a form of swordsmanship in which one strikes down an attacking opponent with one blow of the sword quickly drawn out of its sheath, whether the practitioner is sitting or walking.