D-block (for diffuse) elements consist of the transition metals (group 3-12 on the periodic table) in which the outermost electron shell is the D orbital. D-block elements form at least one stable ion with an incompletely filled electron subshell.
...
German-Dutch school of the fourteenth and fifteenth
centuries, and with the "Confessions" of Augustine
and John Bunyan's Pilgrim's Progress it occupies a
front ...