Explanation of words

It can't be helped, if you like stairs you talk a lot about them. And it may happen that we who work with stairs all day long use words that seem incomprehensible. Please ask us to explain, or use this mini-explanation of words to decipher.
  
Anticlockwise stairway: A stairway that viewed from below winds to the left is an anticlockwise stair.
Baluster: Another name for the posts (laths) in the railing.
Block step: The first tread of the stairs, made slightly wider than the others to give a more welcoming feeling.
Child safety list: In an open stairway (without risers) a list is fitted under each tread to prevent children from creeping under and fastening.
Clockwise stair: A stairway that viewed from below winds to the right is a clockwise stair.
Closed stairway:

Refers to stairs with vertical boards (risers) between the treads.

End knob: Round wall handrails can terminate with a turned knob.
Floor structure: Limited normally by the distance between ceiling and surface of the floor above.
Floor structure covering: The board that is sometimes used to cover the floor structure.
Floor structure opening: The opening between storeys where the stairs are placed.
Free stringer: Refers to a stringer not fitted against a wall.
Inner stringer railing: Refers usually to railing of inner curve
Inner stringer: Refers to stringer of inner winding, usually suspended freely but not always.
Newel: The sturdy posts at the top or bottom of a flight of stairs, sometimes also fitted in corners of the stairway.
Outer stringer: Stringer facing outward.
Outer stringer: Refers to stringer on outer winding. Is often (but not always) fitted on the wall.
Outer stringer rail: Railing on outer winding.
Riser: The vertical board between treads of a closed stairway.
Side stringer: See stringer.
Side beam: The wooden beam in which the treads are secured (or on top). Some stairs have no side beams.
Stringer: A long beam used for structural purposes.
Tread profile: The front edge of treads can be made with various profiles
Under rail: The joist on which the balusters stand.
Underlying string: Stringer with treads fixed on top.
Under rail: Bottom rail.
Upper rail: The handrail fitted on the balusters.
Wall handrail: Handrail secured to the wall, for stairs of which one side runs along a wall.