To veganize something means to make it suitable for vegans. The most common thing that goes through such process is food. For example, meat in recipes is changed into soy meat or seitan, and milk into soy milk. Some foods can be veganized very easily, while others require more unusual ingredients. Some vegan versions of non-vegan foods are even discovered by making many experiments or purely by accident. E.g. did you know that you can get fluffy meringue-like fluff by simply whipping boiled flaxseeds? Apparently that is true.