Maynard is prefers to be mysterious about the inner meanings of many of the songs he writes and the terms he uses, encouraging fans to actually go and figure it out for themselves. Of the vague information he will give out, this is what he says about the meaning of the word Ænima:

"The word anima is a Jungian term (from noted psychologist Carl Gustav Jung) meaning soul, while an enema is an anal douche."
He adds that this doesn't denote merely a cleansing of the soul, of sorts, "It's more of a contemporary version of that. It's about change, cleaning out the house to refurbish or redecorate and start over."

courtesy of Maynard himself and