On the question of the grammaticalisation of edin in the field of indefiniteness

This research article revisits the linguistic problem of whether edin, edna, edno, edni in the Bulgarian language are forms of a grammaticalised indefinite article which expresses the meaning of ‘specific indefiniteness’. In order to achieve the objectives of my research, I apply the principle of obligatoriness when examining edin, edna, edno, edni ’s semantic features and usage limits. In my article, I also present and compare some hierarchical patterns related to the development of the indefinite article in Bulgarian and attempt to determine its specific features.