The paper examines the frequency of words of Lithuanian origin in selected, recently published, Polish language dictionaries. The conducted research shows that the frequency of such words is low. There are only three Lithuanisms in the Słownik etymologiczny języka polskiego by W. Boryś and in the Słownik etymologiczny języka polskiego by K. Długosz-Kurczabowa there are none. The low frequency of these words is discussed in many scholarly works, both those on Polish literary language and those on the Polish language in the Kresy area (the easter borderlands). This paper tries to establish the reasons behind this situation. The reasons are, as the subject literature shows, historical, geographical, practical, aesthetic, cultural and administrative in nature.