When we complete a rope pattern, particularly one where we are following someone else pattern - we are likely to have some rope left over. This left over rope is known by a variety of names some of which are fairly netural some of which show a particular approach to shibari.
Amatta Nawa 余った 縄 : 'leftover rope' Amatta means exceeding.
Kazari nawa 飾り縄: decorative rope, used to refer to decoration added to the end of rope pattern to use up leftover rope.
Mudanawa 無駄縄: 'useless/wasted rope' This can be used to either refer to rope that is left over at the end of a tie that hasn't been incorporated into a pattern, or the inefficient use of rope to bind someone resulting in rope being used without function.
Nawajiri 縄尻: 'rope tail/end'. This refers to the loose end of the rope remaining after a pattern has been completed. Some people incorporate this rope within the rope pattern, while others use this to tug on and apply tension. Haruki Yukimura saw the use of the nawajiri to communicate with the person in rope as being an essential part of his style of tying.