fool's errand

NOUN
13 LETTERS · 2 SYLLABLES · STARTS WITH F

fool's errand is a valid 13-letter word worth 15 points in Scrabble and 17 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
F4O1O1L1'0S1E1R1R1A1N1D2
4 + 1 + 1 + 1 + 0 + 1 + 0 + 1 + 1 + 1 + 1 + 1 + 2 =15 PTS
DOUBLE WORD → 30TRIPLE WORD → 45
MEANING

What does fool's errand mean?

NOUN · 1 SENSE
1

A fruitless mission.