The practice of a group of 3 or more men lined up behind one another, where each man is being buggered
from behind whilst simultaneously buggering
the man in front. The phrase is thought to have come in to usage when such homosexual practices were widespread in monasteries
in the early Tudor period. The practice was rumoured to be part of a sordid initiation ceremony where novice monks would take the front of the Abbots Chain and be forced to felate
as he stood on a ceremonial footstool. Long held to be one of the minor reasons Henry VIII began to sack many monasteries during his reign, after he was not invited to a mass Abbots Chain in Westmister Abbey organised by the Archbishop of Canterbury. The practice is quite common in certain specialist clubs in London, particularly in the Muswell Hill area.
If you had Graham Norton being buggered by Dale Winton who in turn was being entered by George Michael, whose anus was being pentrated by Michael Barrymore, who himself was having his bottom pounded by Rupert Everett, you would be witnessing what is known as an Abbots Chain.