The term 'massive group' can be summarized by the word 'HORDE, ' which is a five-letter word. A HORDE is a large, often unorganized group of people or animals. It is typically used to describe a large number of people or animals that are moving together in a chaotic manner. Historically, hordes were used to describe nomadic groups of people or animals that moved from place to place in search of food and resources. In modern times, the term is often used to describe large crowds of people or animals that are gathered together for a common purpose.