The paper exemplifies a unique attempt to trace the evolution of the preposition and the adverb ABOUT as initial and transposed categories. The study focuses on the development of both interwoven categories since 850 and up to the early 21st century and covers 16 time spans.
The paper proves that despite being registered during 850–950 as the representative of both categories, ABOUT initially represented the category of preposition. The research showcases that since its functional transposition in Old English, the category of the adverb ABOUT has been undergoing a continuous decrease, which is significantly enhanced in the second half of Late Modern English and reaches its peak in the early 21st century. The reasons for the growth of the preposition ABOUT lie not in the phenomenon of transposition but in the emergence of a new function: ‘in reference to’, which developed in Early Modern English and provided the impetus for a further increase of the preposition ABOUT.