'Lintel' in the Bible
They're to take some of the blood and put it on the two doorposts and on the lintel of the houses where they eat the lamb.
Take a bundle of hyssop and dip it in the blood that is in the basin, and apply some of the blood in the basin to the lintel and the two doorposts. None of you is to go out of the doorway of his house until morning,
because the LORD will pass through to strike down the Egyptians, and when he sees the blood on the lintel and the two doorposts, the LORD will pass over the doorway, and won't allow the destroyer to enter your houses to strike you down.