Yeah, I have seen the internet definitions saying it means Jesus Christ.
I think Dominions uses the word in a different context. In one of my Religions classes, Pantokrator had a different meaning. It meant all powerful, usually used in the context of an earlier supreme diety.
And the link you posted supports this somewhat. One of the definitions listed actually says :
The most common translation is "Almighty" or "All-powerful." In this understanding, Pantokrator is a compound word formed from the Greek words for "all" and the noun "strength" (κρατος

. This is often understood in terms of potential power; i.e., able to do anything, or omnipotentent.
"Another translation is "Ruler of All" or "Sustainer of the World." In this understanding, Pantokrator is a compound word formed from the Greek for "all" and the verb meaning "To accomplish something" or "to sustain something" (κρατεω

. This translation speaks more to God's actual power; i.e., God does everything (as opposed to God can do everything)."
Which I think would have fit Chronus and Ymir (Especially) nicely before the other gods came along.
The internet is not the end all - be all of definitions and meanings of words. Take the word "myth" for instance. One of our assignments was to define "myth" in the context of religion. The correct answer was "A story (True or False) that reveals a profound truth." or some junk. None of us found that definition on the internet, so no soup for us.