The term Henotheism (and the derivate ‘henotheistic’) is a real word.
For example, you may find a definition of Henotheism in the following on-line dictionaries:
http://ancienthistory.about.com/...gyptmyth/g/henotheism.htmHenotheism Definition & Meaning - Merriam-Websterhenotheism | religion | BritannicaHenotheism - definition of henotheism by The Free Dictionaryhttp://www.yourdictionary.com/henotheismhenotheism | Etymology, origin and meaning of henotheism by etymonline
But, what is more important than mere words are the concepts included in the three ideas of what we call Monotheism, Henotheism, and Politheism (these definitions are not always well defined!)
You may also safely forget these words and, instead, focus yourselves on these three ideal concepts:
Concept A: In the whole universe exists only one god. I worship this sole god.
Concept B: In the universe exist a number of gods. But I worship only one of these
Concept C: In the universe exist a number of gods. I worship all of them
Now, is not important if the word sequence ‘Monotheism’-‘Henotheism’-‘Politheism’ closely fits with the sequence ‘Concept A’-‘Concept B’-‘Concept C’ (shown before).
The pivotal point is:
Is — for example — Christianity more closely described like a Religion that sticks on the Concept A, the Concept B, or the Concept C?
Virtually all Christians immediately would rule out the Concept C from the (mathematical) set of Christianity.
But, what about the remaining Concepts, A and B?
Christianity may be considered to be inside the Concept A?
Or, it is more appropriate to consider Christianity like a part of the Concept B?
I think this is an important question inside the thread Bible Study.