(of a coach) keep (a college athlete) out of university competition for a year in order to develop the athlete's skills and extend their period of playing eligibility

he came to Ohio State as a defensive lineman and was redshirted in 2010

delay the start of formal schooling for (a child) by one year, typically so as to avoid a situation in which the child is among the youngest in their class

here are some things to think about before deciding whether or not to redshirt your kindergartener