'Cover' in the Bible

“Make yourself an ark of gopher wood. Make rooms in the ark, and cover it with pitch inside and outside.

In the six hundred and first year, in the first month, on the first day of the month, the water that had covered the earth was dried up. Then Noah removed the ark’s cover and saw that the surface of the ground was drying.

Then Judah said to his brothers, “What do we gain if we kill our brother and cover up his blood?