atom smasher

NOUN
12 LETTERS · 3 SYLLABLES · STARTS WITH A

atom smasher is a valid 12-letter word worth 18 points in Scrabble and 19 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
A1T1O1M3S1M3A1S1H4E1R1
1 + 1 + 1 + 3 + 0 + 1 + 3 + 1 + 1 + 4 + 1 + 1 =18 PTS
DOUBLE WORD → 36TRIPLE WORD → 54
MEANING

What does atom smasher mean?