publishing firm

NOUN
15 LETTERS · STARTS WITH P

publishing firm is a valid 15-letter word worth 27 points in Scrabble and 33 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
P3U1B3L1I1S1H4I1N1G2F4I1R1M3
3 + 1 + 3 + 1 + 1 + 1 + 4 + 1 + 1 + 2 + 0 + 4 + 1 + 1 + 3 =27 PTS
DOUBLE WORD → 54TRIPLE WORD → 81
MEANING

What does publishing firm mean?