The term 'right-hand page of an open book' can be summarized as the recto, which is a five letter word. The recto is the right-hand page of an open book when the book is held with the spine facing away from the reader. This is in contrast to the verso, which is the left-hand page of an open book. The recto and verso are terms used in the printing industry to refer to the two sides of a single sheet of paper.