The crossword solution for the term 'Warrior Prefix' is ECO, which stands for ecology. Ecology is the study of the interactions between living organisms and their environment, and it is often used to refer to environmental protection and conservation. ECO is also used as a prefix to denote something related to the environment or ecology, such as eco-friendly products or eco-tourism. In this context, ECO can be seen as a warrior prefix, as it is associated with the fight to protect the environment.