formative cell

NOUN
14 LETTERS · STARTS WITH F

formative cell is a valid 14-letter word worth 23 points in Scrabble and 28 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
F4O1R1M3A1T1I1V4E1C3E1L1L1
4 + 1 + 1 + 3 + 1 + 1 + 1 + 4 + 1 + 0 + 3 + 1 + 1 + 1 =23 PTS
DOUBLE WORD → 46TRIPLE WORD → 69
MEANING

What does formative cell mean?