impurity atom

13 LETTERS · STARTS WITH I

impurity atom is a valid 13-letter word worth 21 points in Scrabble and 24 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

I1M3P3U1R1I1T1Y4A1T1O1M3

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

DOUBLE WORD → 42TRIPLE WORD → 63

MEANING

What does impurity atom mean?