Slovakia
Slovakia's name in theory means the „Land of the Slavs“ (Slovensko in Slovak language, stemming from the older form Sloven/Slovienin). As such, it is a cognate of the words Slovenia and Slavonia. In medieval Latin, German sources and even some Slavic sources, the same name has often been used for Slovaks, Slovenes, Slavonians and Slavs in general.
According to one of the theories, between 13th and 14th century a new form of national name formed for the ancestors of the Slovaks, possibly due to foreign influence – the Czech word Slovák (in medieval sources from 1291 onward). This form slowly replaced the name for the male members of the community, but the female name (Slovenka), reference to the lands inhabited (Slovensko) and the name of the language (slovenčina) all remained the same, with their base in the older form (compare to Slovenian counterparts). Most foreign translations tends to stem from this newer form (Slovakia in English, Slowakei in German, Slovaquie in French, etc.).
In medieval Latin sources, terms Slavus, Slavonia or Slavorum (and more variants, from as early as 1029) has been used for them.
In German sources, names for the Slovak lands were Windenland or Windishen landen (early 15th century), later also the form „Slovakia, Schlowakei“ starts to appear (from 16th century). The present Slovak form „Slovensko“ is first attested in the year 1675.