negative lens

13 LETTERS · STARTS WITH N

negative lens is a valid 13-letter word worth 16 points in Scrabble and 21 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

N1E1G2A1T1I1V4E1L1E1N1S1

1 + 1 + 2 + 1 + 1 + 1 + 4 + 1 + 0 + 1 + 1 + 1 + 1 =16 PTS

DOUBLE WORD → 32TRIPLE WORD → 48

MEANING

What does negative lens mean?