Unusual Balkan? Dagger

[Atlantia]

Originally Posted by Dmitry

There's no difference between a knife and a dagger then...

Well, for sure the vast majority of daggers are knives, and some knives are daggers

Dictionary definitions seem fairly similar:
'Short pointed knife: a short pointed knife used as a weapon' (Encarta)
'Stabbing weapon with short pointed and edged blade' (Oxford)

Obviously the item in question IS a knife, but to me it goes without saying that it's a dagger also.
So either designation is technically correct in my view.