Names of Kosovo

The name Kosovo (as referred to in this spelling) is the most frequently used form in English when discussing the region in question. The Albanian spelling "Kosova" has lesser currency. The alternative spellings "Cossovo" and "Kossovo" were frequently used until the early 20th century.
Kosovo.
Kosovo () is the Serbian neuter possessive adjective of "kos" (), meaning "blackbird"; "-ovo" being an adjectival suffix – it is short for the region named the "field of the blackbird" (), the Kosovo field, the site of the 1389 battle between the army of Serbian Prince Lazar and the Ottoman Army, which ended in an Ottoman victory and Serbian decline. The name "Kosovo" Kos- is found in hundreds of Slavic locations. The cognate of Proto-Slavic kosь is Ancient Greek κόσσυφος.
Another explanation is that the word root "kos" stems from the root of the Serbian word (English to scythe, to mow, Russian kosit’, косить, Polish kosić, češ. kosit, Slovakian kositi, Romanian cosi), so that the toponym would mean a place for mowing or yielding good hay. Over 90 per cent of terms used in agriculture, names of settlements and geographical names in today’s Kosovo are of Serb origin. 
In Albanian, the variant name is "Kosova" (definite "Kosovë"), a borrowing from Serbian. Due to having borrowed it, some Albanian nationalists suggested "Dardania" as a substitute in the 1990s.
Arnavudluk (Albania).
Kosovo was part of the Ottoman state for 457 years. 
Ottoman traveller Evliya Çelebi, who went to the area in 1660 referred to central Kosovo as "Arnavud" (آرناوود) and noted that in Vučitrn its inhabitants were speakers of Albanian or Turkish and few spoke "Boşnakca". The highlands around the Tetovo, Peja and Prizren areas Çelebi considered as being the "mountains of Arnavudluk". Çelebi referred to the "mountains of Peja" as being in Arnavudluk and considered the Ibar river that converged in Mitrovica as forming Kosovo's border with Bosnia. He viewed the "Kılab" or Lab river as having its source in Arnavudluk and by extension the Sitnica as being part of that river. Çelebi also included the central mountains of Kosovo within Arnavudluk.
During Ottoman rule the area of Kosovo was referred to as "Arnavudluk" (آرناوودلق) meaning Albania by the empire in its documents such as those dating from the eighteenth century.
Gegalik (Gegënia).
In the late Ottoman period Albanians claimed the sancaks of Yeni Pazar (Novi Pazar), Ipek (Peja), Prizren, Priștine (Pristina) and Üsküp (Skopje) which were all within Kosovo Vilayet as forming part of "Gegalık" or Land of the Gegs, a term named after Gheg Albanians who inhabited the area.
Dardania.
There is a theory within linguistics that the name Dardania used in ancient times for the area of Kosovo is derived from the Albanian word dardhë, meaning "pear".
Due to its Slavic (Serbian) character, Kosovo Albanian leader Ibrahim Rugova supported a name change to "Dardania", in reference to the ancient kingdom and later-turned Roman province. Albanian nationalists seek to remove Serbian terminology (and toponomy) in Kosovo. It, however, did not enter into general usage.
Kosovo and Metohija.
The name "Kosovo and Metohija" was used for the autonomous province in Yugoslav Serbia since its creation in 1945 until 1968, when the term "Metohija" was dropped. In 1990, the name was reversed to "Kosovo and Metohija". After the Kosovo War, the United Nations mission used only "Kosovo" as the name of the province.