The term 'FIRST EPISODE' can be broken down into two words, 'PILOT' and 'DEBUT'. The word 'PILOT' is a 5 letter word that refers to the first episode of a television series or film. It is usually used to introduce the characters and setting of the show. The word 'DEBUT' is also a 5 letter word and it means the first appearance of something, such as a person or product. In this case, it is referring to the first episode of a television series or film. Together, these two words refer to the first episode of a television series or film, which is often used to introduce the characters and setting of the show.