I can't figure out what language that is from. I would have guessed it is a feminine form patterned after anIsha (from Sankrit: privative an- +
Isha from Ish, to possess: i.e., supreme being, literally one without a master). anIshA itself is not Sanskrit (or rather it is: meaning helplessness, literally absence of mastery, but that is most likely not what is intended).
Of course, it may be of a different origin.