def cell_face_areaness(cell, target_areas):
    """Compute the areaness of every face of a mesh.

    Parameters
    ----------
    cell : Mesh
        Cell as a mesh object.
    target_areas : dict
        Dictionary of target areas.

    Returns
    -------
    dict
        A dictionary of area deviation for each face of the mesh.

    """
    areaness_dict = {}

    for fkey in target_areas:
        area = cell.face_area(fkey)
        areaness_dict[fkey] = abs(target_areas[fkey] - area)

    return areaness_dict