double integral

15 LETTERS · STARTS WITH D

double integral is a valid 15-letter word worth 18 points in Scrabble and 24 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

D2O1U1B3L1E1I1N1T1E1G2R1A1L1

2 + 1 + 1 + 3 + 1 + 1 + 0 + 1 + 1 + 1 + 1 + 2 + 1 + 1 + 1 =18 PTS

DOUBLE WORD → 36TRIPLE WORD → 54

MEANING

What does double integral mean?