The Most Similar Languages to Lithuanian

Lithuanian, a Baltic language, is part of the Indo-European family. Despite its unique characteristics, it shares certain similarities with several other languages. According to the eLinguistics.net analysis using specific software modules to assess linguistic relationships, the five languages most similar to Lithuanian are Latvian, Slovenian, Bulgarian, Slovak, and Polish.

1. Latvia (64.3)
   Along with Lithuanian, Latvian is the other major language that belongs to the Baltic group. These two languages are the closest relatives, sharing a significant amount of vocabulary, grammatical structures, and phonetic features. Both languages have preserved many archaic features not found in other Indo-European languages.
2. Slovenian (61.2)
   Slovenian, a South Slavic language, shows a few similarities with Lithuanian. Although the vocabulary and phonology differ significantly due to their separate branches within the Indo-European family, both languages exhibit complex inflectional systems. Their nouns, pronouns, and adjectives change their form depending on their grammatical role in the sentence.
3. Bulgarian (60.9)
   Bulgarian is another Slavic language on this list, so it shares some traits with Lithuanian. These include aspects such as certain verb forms and inflections. However, Bulgarian has undergone significant changes over the centuries, such as the loss of noun cases, which sets it apart from Lithuanian. Despite these differences, there are deep-rooted connections between them.
4. Slovak (60.1)
   Slovak is the highest West Slavic language on this list. It displays similarities with Lithuanian in terms of certain grammatical constructions and vocabulary words that can be traced back to their common origins in Eastern Europe.
5. Polish (59.9)
   Poland borders Lithuania, so it is no wonder these countries share some similar vocabulary and terminology. While Polish and Lithuanian have diverged significantly over time, they still share some significant features. The historical interactions and proximity of Poland and Lithuania have also led to lexical borrowings between the two languages.

(to be considered for the list, the language must be spoken by at least one million people)