This study combines historical comparative linguistics with the analysis of Khitan Small Script textual materials to examine the semantic functions of the word
m-er
and its plural form
m-ci
, which correspond to the Chinese concept of Dao (
dao
道
). Through a systematic collation and contextual analysis of examples from Khitan Small Script epitaphs and related literary sources, this article argues that
m-er
and
m-ci
exhibit layered semantic features in the Khitan Small Script corpus, characterized by the coexistence of abstract and concrete meanings. Furthermore, through a comparison of interchangeable usages of
sh-al-s
and
m-er
in Khitan Small Script texts, this study examines their semantic layers, investigating both their shared core meanings and semantic distinctions.