Step (5)
(Other definitions for aside that I've seen before include "Aides (anag.)" , "kept in reserve" , "Whispered comment" , "(Turn) off main path" , "Separately" .)
'step' is the definition.
(I know that step can be written as tread)
This is the entire clue.
(Other definitions for tread that I've seen before include "Walk heavily" , "Walk along" , "Put one's foot down!" , "Walk or step like pattern on tyre" , "Surface of car tyre" .)
'step' is the definition.
(a single step in a staircase)
This is all the clue.
(Other definitions for stair that I've seen before include "Step in house" , "single step in a series" , "Support on which to step" , "Way between floors" , "One of a flight of steps" .)
'step' is the definition.
(I know that step can be written as measure)
This is all the clue.
(Other definitions for measure that I've seen before include "See 6" , "Extent" , "Show something's dimensions" , "Standard unit; dance" , "capacity" .)
'step' is the definition.
(I know that step can be written as pace)
This is all the clue.
(Other definitions for pace that I've seen before include "Part of step" , "Gait" , "speed of movement" , "Clip" , "a certain distance" .)
'step' is the definition.
(I know that step can be written as stride)
This is all the clue.
(Other definitions for stride that I've seen before include "style of jazz piano" , "Long decisive step" , "A lengthy step" , "Long pace" , "Step out energetically" .)