Plural form of sideline. The lines marking the edges.(noun)
The area or areas next to but outside a playing area.(noun)
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Use "sidelines" in a sentence
"USA giving support and close monitoring at the sidelines is all we have to do."
"Everyone, from Contador to UCI president Pat McQuaid to Tour director Christian Prudhomme to all of us on the sidelines, is hoping the case will be settled quickly."
"One of my sidelines is preceptor for students at the University of Wyoming."