Maybe you misunderstood me, but I meant the legal mechanism by which you can defer publication/examination of a filed patent for over 20 years before having it

Maybe you misunderstood me, but I meant the legal mechanism by which you can defer publication/examination of a filed patent for over 20 years before having it granted. It seems to me that that is a de facto increase of the patent term, so I was wondering whether there's a statutory provision for this and if so, where.