control group

13 LETTERS · STARTS WITH C

control group is a valid 13-letter word worth 17 points in Scrabble and 23 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

C3O1N1T1R1O1L1G2R1O1U1P3

3 + 1 + 1 + 1 + 1 + 1 + 1 + 0 + 2 + 1 + 1 + 1 + 3 =17 PTS

DOUBLE WORD → 34TRIPLE WORD → 51

MEANING

What does control group mean?