PREFIX
(加在名词之前构成动词)表示“除去”，“除掉”
De- is added to a noun in order to make it a verb referring to the removal of the thing described by the noun.
例句
I've defrosted the freezer...
我已经给冷冻柜除过霜了。
The fires are likely to permanently deforest the land.
这些火灾很可能会彻底毁掉这片土地上的森林。