1) Corbel step 2) Corbie-step 3) Crow step 4) Stair 5) Step 1) Crowstep 
• (n.) One of the steps in which a gable wall is often finished in place of a continuous slope; -- also called crowstep.
Stepped-end gable 
Cor'bie·step` noun (Architecture) One of the steps in which a gable wall is often finished in place of a continuous slope; -- also called crowstep . 
In architecture, corbiesteps or crowsteps are the steps in which a gable wall is often finished in place of a continuous slope. They are common in old Scotch architecture, into which they were probably introduced from France, and also in old houses in Flanders, Holland and Germany.
any of a series of steplike portions of a masonry gable that terminate the gable above the surface of the roof. Also called