This study on the terminology of vocabulary in mother tongue teaching focused on a total of 25 concepts which are gathered from the literature on mother tongue teaching and considered to be widely utilized in the academic studies in the relevant field. In this regard, the study examined the concepts of "Word, Concept, Term, Vocabulary, Corpus, Word Family, Conceptual Field (Linguistic Field), Word Quality, Word Frequency, Word Extensiveness, Word Type, Receptive Vocabulary, Productive Vocabulary, Depth, Width, Weight, Semantic Field, Semantic Value, Hyponymy, Chroneme Difference, Lexical Field, Mental Lexicon, Lexeme, Morpheme", which can feature the field of vocabulary in mother tongue teaching in the educational field and therefore should be considered as keystones in developing a common terminology language. The above-mentioned concepts are discussed within Turkish Language teaching as mother tongue and in regard to their functions in the studies on vocabulary. The study concluded that the extensive use of the available terminology is necessary in order to feature the data obtained from the studies on vocabulary in the field of mother tongue teaching. The wide utilization of these concepts in the literature of mother tongue teaching is of critical importance in developing a common terminology.