Interdiscursivity

Interdiscursivity is a concept in discourse studies that refers to the way a single textual or spoken artifact draws on and negotiates multiple discourses. It focuses on how voices, norms, genres, and professional styles from different social fields are combined within one communicative act. Unlike a strict notion of intertextuality, which foregrounds textual quotation and reference, interdiscursivity highlights the strategic positioning of the speaker/listener relative to different existing discourses and their associated ideologies. Through interdiscursivity, a text can enact authority by citing legal, scientific, political, or media discourses, while simultaneously appealing to everyday or consumer discourses.

Interdiscursivity surfaces in political speeches that embed legal or scientific language to frame issues as legitimate or technocratic; in news reporting that quote experts and NGOs to balance or legitimate coverage; and in advertising that mix medical, cultural, and consumer discourses to shape consumer identities. It also appears in everyday talk and online communication, where genres cross boundaries and different registers are invoked for stance-taking, persuasion, or identity construction.

Analytically, scholars examine interdiscursivity within critical discourse analysis, genre analysis, and discourse-historical approaches by tracing references, quotations, frame shifts, and shifts in voice or audience. Studying interdiscursivity helps reveal how knowledge, power, and social legitimation circulate across discourses, and how speakers marshal multiple voices to achieve rhetorical or ideological aims.