The Abaza language is a language with a recent system of writing, and on that ground many issues of lexicology including archaisms have not been studied monographically. The article presents the systematization of a particular case of archaisms. On the basis of more than 600 obsolete words extracted by the authors from the lexicographical sources, texts of Abaza folklore, artistic and publicistic literature and field materials, analysis of its features and classification of archaisms, the main reasons for the transition of lexems from active to passive vocabulary are revealed. The study confirmed the well-known position in General lexicology that the main trigger for archaization of lexemes is a decrease in the level of functional relevance of the word, due to the loss of relevance of the denoted (denotation) of this unit. Depending on the reason for transition to a passive vocabulary, several groups of archaisms are distinguished: a) proper lexical archaisms , b) lexical-semantic archaisms, с) lexical-phonetic archaisms, d) lexical-morphological archaisms, and e) lexical-word-forming archaisms.
The process of word archaization is influenced by both linguistic and extralinguistic factors. Due to the nature of the Abaza literary language, which is recently put into writing, the concept of «archaism» or «obsolete words» is different for different generations of Abazins. Many words related to the vocabulary of agriculture, cattle breeding, sewing, etc. are already archaisms for modern youth, while for the adult (elderly) population they are still commonly used. The process of archaization of words is influenced by both linguistic and extralinguistic factors.