spill the beans

VERB
15 LETTERS · STARTS WITH S

spill the beans is a valid 15-letter word worth 20 points in Scrabble and 24 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
S1P3I1L1L1T1H4E1B3E1A1N1S1
1 + 3 + 1 + 1 + 1 + 0 + 1 + 4 + 1 + 0 + 3 + 1 + 1 + 1 + 1 =20 PTS
DOUBLE WORD → 40TRIPLE WORD → 60
MEANING

What does spill the beans mean?