Sorry, Luci45, I should have said Eurasian elk, which is indeed a synonym for moose. http://en.wikipedia.org/wiki/Eurasian_elk
You are quite right: a plain old elk isn't the same as a moose. It's apparently the same as a wapiti. http://en.wikipedia.org/wiki/Elk
I gather that when Europeans (English-speaking) first arrived in North America, the first kind of truly big deer they encountered, was the wapiti; which they called the elk -- after the Eurasian elk, which they knew from back east of the Atlantic. They later found that the same species as the Eurasian elk, lives in N. America too; so to name that one, they needed to borrow the Native American word for it, "moose".
Dreadful joke, follows -- from "Punch", the British supposedly comical magazine. "Punch" 's humour is in fact often pretty laboured; and was more so, about a hundred years ago -- the date of this offering (which revolves around the peculiarities of the Scottish accent).
There's a cartoon of two loggers, deep in the Canadian forest: Sandy, an immigrant just off the boat from Scotland, and old-timer Jake. A moose is walking past, just minding its own business.
Sandy: "Mon ! Whit's yon thing, for heaven's sake?"
Jake: "That's just a young moose -- nothing to worry about."
Sandy: "Och, havers ! If yon's a young moose, then show me ane o' yer auld rats !"