What is the crossword answer for the clue: Start of a series

ABC - a 3 letter word may be the answer you are looking for!

ONE - a 3 letter word may be the answer you are looking for!

ABCD - a 4 letter word may be the answer you are looking for!

ABCDE - a 5 letter word may be the answer you are looking for!

ALPHA - a 5 letter word may be the answer you are looking for!

PARTI - a 5 letter word may be the answer you are looking for!

OPENER - a 6 letter word may be the answer you are looking for!

PARTONE - a 7 letter word may be the answer you are looking for!

TELEVISIONPILOT - a 15 letter word may be the answer you are looking for!

PILOT - a 5 letter word may be the answer you are looking for!

Start of a series

3 Character Answers:

ABC

ONE

4 Character Answers:

ABCD

5 Character Answers:

ABCDE

ALPHA

PARTI

PILOT

6 Character Answers:

OPENER

7 Character Answers:

PARTONE

15 Character Answers:

TELEVISIONPILOT