Wiktionary
decolour
vb. (context transitive English) To deprive of colour; to bleach.
WordNet
decolour
v. remove color from; "The sun bleached the red shirt" [syn: bleach, bleach out, decolor, decolorize, decolourize, decolorise, decolourise, discolorize, discolourise, discolorise]