accumulate

VERB /ə'kjumjə,leɪt/
10 LETTERS · 4 SYLLABLES · STARTS WITH A

accumulate is a valid 10-letter word worth 16 points in Scrabble and 22 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
A1C3C3U1M3U1L1A1T1E1
1 + 3 + 3 + 1 + 3 + 1 + 1 + 1 + 1 + 1 =16 PTS
DOUBLE WORD → 32TRIPLE WORD → 48
MEANING

What does accumulate mean?