'Uncovering' in the Bible

But see to it, when he goes to rest, that you take note of the place where he is sleeping, and go in there, and, uncovering his feet, take your place by him; and he will say what you are to do.

Now when Boaz had taken meat and drink, and his heart was glad, he went to take his rest at the end of the mass of grain; then she came softly and, uncovering his feet, went to rest.