sideline

A line along either of the two sides of a playing court or field, marking its limits.

The space outside such limits, occupied by coaches, inactive players, and spectators.

The position or point of view of those who observe rather than participate in an activity.

A subsidiary line of merchandise.

An activity pursued in addition to one’s regular occupation.

To remove or keep from active participation.

A line pertaining or attached to the side of something; specifically, in the plural, lines by which the fore and hind feet on the same side of a horse or other animal are tied to prevent straying or escape.

A line or course of business aside from or additional to one’s regular occupation.

To hobble, as a horse.