riser

nouns

a person who rises (especially from bed)
"he's usually a late riser"
is derived from
is derived from
is a type of (narrower)
a human being
"there was too much for one person to do"
a vertical pipe in a building
structural member consisting of the vertical part of a stair or step
is a part of
support consisting of a place to rest the foot while ascending or descending a stairway
"he paused on the bottom step"
is a type of (narrower)
support that is a constituent part of any structure or building