An octagon inscription is a type of engraving or carving that is done on an octagonal surface. It is usually used to create decorative designs, symbols, or words on the surface. The term 'octagon inscription' is derived from the shape of the surface, which is an eight-sided polygon. This type of engraving is often used in jewelry, architecture, and other decorative arts. The answer to the crossword puzzle is STOP, which is a four-letter word.