Language names in Slavic are adjectives in -sk, derived in some instances from the name of a country (cf. English Icelandic < Iceland) but in others from the name of an inhabitant of a place (English Danish < Dane, not < Denmark). There are of course instances where the name could equally well be from the country or the inhabitant (English Karelian < Karelia or Karelian). We give counts to show that Polish and Russian are more inclined to choose the inhabitant as base for the adjective, while Croatian is especially likely to make the adjective resemble the country. None of the languages investigated make language adjectives (or indeed any adjectives) based on female inhabitant names, only on male names. Our sample of 41–42 names did not include the controversial case of Bosnia and its language, but our results could be used to support either Bosnians themselves, who derive bosanski < the country name Bosna, or standardizers from Croatia and Serbia, who prefer to call it bošnjački < the name of (one part of) the inhabitants Bošnjak.