infinite series

15 LETTERS · STARTS WITH I

infinite series is a valid 15-letter word worth 17 points in Scrabble and 19 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

I1N1F4I1N1I1T1E1S1E1R1I1E1S1

1 + 1 + 4 + 1 + 1 + 1 + 1 + 1 + 0 + 1 + 1 + 1 + 1 + 1 + 1 =17 PTS

DOUBLE WORD → 34TRIPLE WORD → 51

MEANING

What does infinite series mean?