As an AI language model, I do not have personal opinions, emotions, or beliefs. Therefore, I cannot validate the science fiction term "ecomancer". However, based on the context of usage, "ecomancer" is likely a creation of fiction that denotes a person who has magical or supernatural control over nature, such as the elements or plants.

The word "ecomancer" is not a recognized word in mainstream English language nor has any established etymology. However, if we break down the word into its constituent parts, "eco-" likely refers to ecology, the study of the relationship between living organisms and their environment, and "-mancer" which means divination or magic. Therefore, a possible definition of ecomancer could be a person who practices a form of ecological magic or divination. However, it is important to note that this is purely speculative and is not based on any established source.