The term 'FIRST OF A SERIES' can be represented by four different crossword solutions: ALPHA (5 letters), OPENER (6 letters), PILOT (5 letters), and PARTI (5 letters). Alpha is the first letter of the Greek alphabet, and is often used to refer to the beginning or the start of something. OPENER is a word that implies the beginning of something, such as the opening of a show or the start of a game. PILOT is a term used to describe the first episode of a television series, which is used to introduce the characters and the setting. Parti is a French word meaning 'PARTY', which can be used to refer to the first installment of a series of events.