ocean bottom

NOUN
12 LETTERS · STARTS WITH O

ocean bottom is a valid 12-letter word worth 17 points in Scrabble and 21 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
O1C3E1A1N1B3O1T1T1O1M3
1 + 3 + 1 + 1 + 1 + 0 + 3 + 1 + 1 + 1 + 1 + 3 =17 PTS
DOUBLE WORD → 34TRIPLE WORD → 51
MEANING

What does ocean bottom mean?