An octet is a group of eight people or things. It is commonly used to refer to a group of eight musicians, such as an octet of string instruments or a vocal octet. Octets are also used in other fields, such as mathematics and chemistry, to refer to a group of eight elements or particles. The term 'eight-piece groupings' is often used interchangeably with 'octets' to refer to any group of eight people or things.