whiten

1. V-T/V-I When something whitens or when you whiten it, it becomes whiter or paler in colour. 變白; 使變白

Her knuckles whiten as she clenches her hands harder. 她的手握得越來(lái)越緊，指節(jié)都變白了。

...toothpastes that whiten teeth. ...增白牙膏。