Ladder: On shipboard, all stairs are called "ladders," except for literal staircases aboard passenger liners. Most "stairs" on a ship are narrow and nearly vertical, hence the name. From the Anglo-Saxon hiaeder, meaning ladder.
[Source: http://www.desertanchor.com/glossary.htm]
The space under a staircase is called a spandrel.
stringers
Handrails or bannisters
Bed room
The staircase along the periodic table is called the "staircase of metalloids" or "zigzag line." It separates the metals on the left from the nonmetals on the right and helps to distinguish between the properties of elements in different regions of the table.
the ships carrying emigrants were called "coffin" ships
Coffin ships were called coffin ships because lots of people died on them
Because they were ships? Do you mean longships? They were long and thin.
The element inside a staircase is commonly referred to as the "stringer." Stringers are the inclined boards that support the treads and risers of the staircase, providing structural integrity and stability. They run along the sides of the staircase and can also be found in the center for wider staircases.
A ships accountant is called a "PURSER"
The decorative wood on a staircase is called "wainscot"
It is usually called a landing.