Is the word ulv a synonym for värg?
or does it apply to a different kind of animal?
Ulv and varg are synonymous, yes. Ulv is more archaic and less common.
Edit: 'Ulv' is related to 'wolf', but I don't think 'varg' has cognates in English outside Tolkiens works.
Only to Old English wearg / wearh, from which Tolkien took the name. Both the Swedish and the Old English come from the same root.
As in werewolf then I presume. So I was wrong after all. There is still (at least) one cognate in the English language!
Not quite- 'were' comes from the Old English 'wer', meaning 'male human'. 'Wearg' and 'wearh' both mean 'wolf'.
'Were' is pronounced something like Modern English 'wear a', whereas the other two are closer to 'warch'. (the 'ch' is pronounced like a German 'ch') and Swedish 'varg' (with a 'w' instead of a 'v').
I've read the 'varg' theory of 'varulv' before, but I agree to the etymology you gave above. It makes perfekt sense in Swedish too.
Just adding for fun that the word värld/"world" is actually a cognate as well - it's comprised of verr and old, meaning "man" and "age"/"growing"/"happening", respectively. The world ålder comes from the latter part, so essentially, a world is a human epoch.
And an older Swedish word for brother-in-law was värbror. :)
We have hundreds and hundreds of words that come from Old Norse, which is great- it makes Swedish and Norwegian a lot easier to learn!
Thankyou for invading us repeatedly for 200 years. :D
I don't know if you've ever looked into Old English, but I'm always presently surprised by how similar it is to Swedish, it's really neat.
I was studying both Old English and Old Norse before I picked up Swedish last year.
You'll find that the further back you go, the closer all of the Germanic languages become. For a long time, Old English and Old Norse were mutually intelligible with a little work.
As I can't sleep I will elaborate a little. 'Ulv' is the original word. People started using 'varg' instead because they were afraid to say 'ulv' out loud. 'Varg' was originally a word for the lowliest kind of murderer. One who kills people in the dark or by strangling, poisoning or other "dishonest" methods. This was 1000 years ago or so. Today 'varg' only means 'wolf'.
I'd like to add to the excellent answers you've already gotten that "ulv" is rarely used at all today. It is essentially archaic.
Still sometimes used, in the saying En ulv i fårakläder - A wolf in sheep's clothing, as the "wolf" part in werewolf - varulv and in the first name Ulf, so even if we'd pretty much never refer to an actual wolf as ulv, it doesn't hurt knowing it. Norwegians and Danes still use "ulv" as the common name for wolf as well.