The term 'topmost point' can be described by two four-letter words: APEX and ACME. APEX is derived from the Latin word for 'SUMMIT' or 'PEAK, ' and is used to refer to the highest point of something, such as a mountain PEAK. ACME is derived from the Greek word for 'highest point, ' and is also used to refer to the highest point of something. Both words are often used to describe the highest point of a structure, such as a building or a mountain.