صفات تک بسامدی در زبان های ایرانی باستان

Iranian languages have historically undergone three diachronic stages of development: Old, Middle, and New. From a historical-linguistic perspective, the Old Iranian period spans from the composition of the Gathas (c. 12th–10th centuries BCE) to the end of the Achaemenid period (c. 300 BCE). This qualitative study was conducted with the aim of identifying and structurally analyzing single-frequency adjectives in Old Iranian languages (Avestan and Old Persian) and addressing the question of what morphological and textual distributional features characterize these adjectives. To this end, all adjectives recorded in Bartholomae’s authoritative dictionary (approximately 4,000 entries) were extracted and selected. After data refinement, single-frequency forms were isolated and subjected to structural analysis. The findings indicate that these adjectives display considerable structural diversity and encompass all adjectival types (simple, derived, compound, and phrasal). These forms were attested exclusively in Avestan texts, and no evidence of them was found in Old Persian, likely due to the limited corpus of surviving materials. The majority of the attested forms, most of which are derived adjectives, occur respectively in the Yasna, Vendidad, Mihr Yasht, Ordibehesht Yasht, Zamyad Yasht, and Ram Yasht. In this study, derived adjectives had the highest frequency with 45 instances, while compound adjectives ranked second with 9 instances.