(Greek kath hena, one by one)
A type of polytheism — characteristic of Vedic religion — in which each god is considered single and supreme for awhile.
1. It is closely related to henotheism, the worship of one god while not rejecting the existence of other gods.
2. The term was coined by the philologist Max Müller.
He coined it in reference to the Vedas; where, according to him, each deity is treated as supreme in turn.
Here's the first OED citation for the term:
"1865 Max Müller Sel. Ess. (1881) II. 137 This surely is not what is commonly understood by polytheism. Yet it would be equally wrong to call it Monotheism. If we must have a name for it I should call it Kathenotheism, or simply Henotheism — i.e. a belief in single gods."