garbage dump

NOUN /ɡɑrbɪdʒ_dəmp/
12 LETTERS · STARTS WITH G

garbage dump is a valid 12-letter word worth 20 points in Scrabble and 26 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
G2A1R1B3A1G2E1D2U1M3P3
2 + 1 + 1 + 3 + 1 + 2 + 1 + 0 + 2 + 1 + 3 + 3 =20 PTS
DOUBLE WORD → 40TRIPLE WORD → 60
MEANING

What does garbage dump mean?