artificial radioactivity

24 LETTERS · STARTS WITH A

artificial radioactivity is a valid 24-letter word worth 37 points in Scrabble and 40 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

A1R1T1I1F4I1C3I1A1L1R1A1D2I1O1A1C3T1I1V4I1T1Y4

1 + 1 + 1 + 1 + 4 + 1 + 3 + 1 + 1 + 1 + 0 + 1 + 1 + 2 + 1 + 1 + 1 + 3 + 1 + 1 + 4 + 1 + 1 + 4 =37 PTS

DOUBLE WORD → 74TRIPLE WORD → 111

MEANING

What does artificial radioactivity mean?