Abstract A central goal in historical sociolinguistics is studying linguistic change. Yet only a modest body of research has addressed obsolescence of dialect features specifically, neither in historical linguistics nor in sociolinguistics. However, studies that focus on waning features demonstrate that they do not abruptly vanish but may undergo diverse trajectories of change. This situation is ideally suited to the methods of language variation and change with appropriate attention to the adjacent fields of dialect grammar and historical approaches to sociolinguistics and dialectology. This paper presents an in-depth framework for studying grammatical dialect features in decline from these combined perspectives. Our aims are to: (1) discover and analyze rare features before they are lost, (2) determine which obsolescent features endure and which fall away, (3) offer theoretical insights into dialect recession and its window on language change, and (4) advance the understanding of why some features persist while others do not. First, we outline a methodology for studying declining dialect features, from identification to analysis, with case studies of relative markers, preterite come , double modals, preverbal did , and verbal – s . Second, we synthesize findings on obsolescent features and the linguistic insights they generate. We will demonstrate that obsolescence follows variegated trajectories, which help resolve linguistic puzzles, historical anomalies, regional/social distinctions, and origin debates. Overall, the study supports greater understanding of processes of change, factors contributing to the decline of forms and functions, and emergence of linguistic innovations. The reasoned, replicable methodology we detail will support future research and offer rewarding outcomes.
Tagliamonte et al. (Mon,) studied this question.