spleenwort

NOUN /splin,wɜrt/
10 LETTERS · 2 SYLLABLES · STARTS WITH S

spleenwort is a valid 10-letter word worth 15 points in Scrabble and 18 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
S1P3L1E1E1N1W4O1R1T1
1 + 3 + 1 + 1 + 1 + 1 + 4 + 1 + 1 + 1 =15 PTS
DOUBLE WORD → 30TRIPLE WORD → 45
MEANING

What does spleenwort mean?