Hoodoo,
Lapin Leuku is actually a Leuku because there isn't any southern Finland leuku style. Calling it Lapin Leuku emphasizes the reginon but there is no need to it IMO.
Yuo can see my favorite Leuku in my "knifepage":
http://www.hut.fi/~renkku/puukko.html
Large leuku ('Large' is not needed if left out as leuku it means blade larger than about 15 cm) is not a puukko. Can't explain why but it isn't a puukko. there are long bladed puukkos but they differ from Leukus blade style. Leukus blade is clearly wider in general and also a bit wider near tip than near handle.
I can't speak saame (My mothers family comes from above arctic circle and had reindeers etc. but non-saame people are majority in all but maybe in two most northest districs in Finland. There are about 4000 native saame people living in Finland). They have a word for this little leuku something like small knife or eating knife....
The blade is about the same as in small puukkos but the handle is about the same as in bigger leukus. I really like the handle style as it suits my hand well (I never stab and when I use tip I'm prepared to squeeze hande harder).
In puukkos the tip is generally a bit pointier but the norther you go the more tip look like this little leuku. In a small leukus blade there is never a blood groove. Blade grind is same as in puukkos...
If you put a puukko blade from northern Finland in a small leukus handle you get little leuku.
Hope this helped
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