The term 'PART OF SOME CHAIRS' can be broken down into two crossword solutions: ARM (3 letters) and SLAT (4 letters). An ARM is a part of a chair that is typically used for support when sitting. It is usually connected to the back of the chair and extends downwards. A SLAT is a thin, flat piece of wood or metal that is used to make up the back of a chair. It is usually connected to the frame of the chair and provides support and stability.