Semicircumference is a mathematical term that refers to half of the circumference of a circle. It is often used in geometry and trigonometry. There are several synonyms that can be used instead of semicircumference. The most commonly used synonym is half-circumference which is frequently used in everyday language. Other synonyms include semicircle perimeter, circle's half-circumference, and half-round. These synonyms can be used interchangeably depending on the context. It is essential to know the correct terminology for concepts in mathematics as it helps in better communication and understanding.