threshold[Anglais]

nom
1 : the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close
2 : the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close
3 : the sill of a door; a horizontal piece of wood or stone that forms the bottom of a doorway and offers support when passing through a doorway