The Serbo-Croatian word krajina derives from Proto-Slavic *krajina, derived from *krajь, meaning "edge", related to *krojiti, "to cut"; the original meaning of krajina thus seems to have been "place at an edge, fringe, borderland", as reflected in the meanings of Church Slavonicкраина, kraina, and Old East Slavicокраина, okraina.
In some South Slavic languages, including Serbo-Croatian and Slovene, the word krajina or its cognate still refers primarily to a border, fringe, or borderland of a country (sometimes with an established military defense), and secondarily to a region, area, or landscape. The word kraj can today mean an end or extremity, or region or area. Archaically extrapolated, it could mean "army" or "war"; this meaning developed from the earlier meaning of "borderland" in a manner analogous to the French word campagne. The term is equal to GermanMark and Frenchmarche.
Bosanska Krajina, around Banja Luka and encompassing a larger area, also on older maps called Turkish Croatia; westwards from Vrbas river, on the NW from Završje (on older maps, Završje is a part of Croazia Turca, Türkisch Kroatien, Török Horvátország )
Drniška krajina, area around the city of Drniš in southern Croatia, in Zagora, to west from Cetinska krajina
Imotska krajina, area around the city of Imotski, in southern Croatia, in Zagora mostly containing Imotsko polje, to east from Cetinska and Omiška krajina, to west from Vrgoračka krajina; also the name of the soccer club from Imotski
Istarska krajina, historical region in western Croatia, central area of peninsula of Istria 
Kninska Krajina, region around Knin in southern Croatia, to north from Drniška krajina and northeast from Cetinska krajina
Neretvanska krajina, historical area westwards from river of Neretva, southwest from župa Imota 
Omiška krajina, region in hinterland of city of Omiš, in Croatian south, in Zagora; to east from Cetinska krajina, to west from Cetinska krajina
municipality of Krajina, a municipality in southern Croatia, located between Split and Imotski, existed from 1912–1945 
Sinjska krajina, area in Zagora, in southern Croatia, around the city of Sinj, west from Livanjski kraj, southeast from Vrlička krajina (sometimes considered as part of Cetinska krajina)
SAO Kninska Krajina, Kninska Krajina since the Yugoslav wars is used by some to signify two regions Knin and its surroundings, and to a larger extent Krajina proper (referring to main portion of Republic of Serb Krajina).
^ abRick Derksen (2008), Etymological Dictionary of the Slavic Inherited Lexicon, Brill: Leiden-Boston, page 244
^ abcde“*krajina” in Oleg Trubačóv (ed.) (1974–), Этимологический словарь славянских языков [Etymological dictionary of Slavic languages], Moscow: Nauka, volume 12, pages 87-88
^Max Vasmer (1986), Etimologičeskij slovarʹ russkogo jazyka [Etymological Dictionary of the Russian Language], in 4 vols (second edition), Moscow: Progress — Translated from German and supplemented by O. N. Trubačóv
^ abGroup of authors (1969). "Кра̏јина". Речник српскохрватскога књижевног језика, vol. 3 (in Serbo-Croatian). Novi Sad/Zagreb: Matica srpska/Matica hrvatska. p. 30.
^Group of authors (1972). "Krajina". In colonel-general Nikola Gažević (ed.). Vojna enciklopedija, vol. 4 (in Serbo-Croatian). Belgrade. p. 681.
Karlo Jurišić, Lepantska pobjeda i makarska Krajina, Adriatica maritima, sv. I, (Lepantska bitka, Udio hrvatskih pomoraca u Lepantskoj bitki 1571. godine), Institut JAZU u Zadru, Zadar, 1974., str. 217., 222., (reference from Morsko prase)