polyester Protestant

I recently was astonished by the following phrase, "Polyester Protestants" being used to describe those whom I have delineated as Anglicans by conviction. This phrase was reported to me by a member of the community in a prestigious institution in Dublin suburbia and is in current use. It is reported to me as being used in that institution by cradle members of the Church of Ireland to describe fellow community members who are Anglicans by conviction.