additive group

14 LETTERS · STARTS WITH A

additive group is a valid 14-letter word worth 21 points in Scrabble and 25 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

A1D2D2I1T1I1V4E1G2R1O1U1P3

1 + 2 + 2 + 1 + 1 + 1 + 4 + 1 + 0 + 2 + 1 + 1 + 1 + 3 =21 PTS

DOUBLE WORD → 42TRIPLE WORD → 63

MEANING

What does additive group mean?