Social distancing is anything that reduces the mingling of people - e.g.:
School closures
Working from home
Reducing public transport use
Preventing gatherings at e.g. sports and other venues
Re the last, it has just been said on Newsnight that a meeting is to be held at Downing St between civil servants, broadcasters, the FA, the organisers of the Six Nations and others to discuss the possibility of holding matches behind closed doors with only television audiences.