noun
definition
A line at the side of something.
definition
Something that is additional or extra or that exists around the edges or margins of a main item.
example
She started the business as a sideline to her regular work and it ended up becoming the greater source of income.
definition
A line for hobbling an animal by connecting the fore and the hind feet of the same side.
definition
A line defining the side boundary of a playing field.
definition
Usually in the plural: the area outside the playing field beyond each sideline.
example
The coach stood on the sidelines and bellowed commands at the team.
definition
The outside or perimeter of any activity.
example
She installed the whole fixture while he simply watched from the sidelines.
definition
A secondary road, especially a byroad at right angles to a main road.