decolourise

VERB /di'kələ,raɪz/
11 LETTERS · STARTS WITH D

decolourise is a valid 11-letter word worth 14 points in Scrabble and 17 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
D2E1C3O1L1O1U1R1I1S1E1
2 + 1 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 =14 PTS
DOUBLE WORD → 28TRIPLE WORD → 42
MEANING

What does decolourise mean?