The proposed research aims to establish causal links between conversational alignment and language change through controlled, ecologically valid experiments. Speakers in conversation often reuse elements of each other’s language, either automatically or through negotiation to form conceptual pacts on terminology (Pickering & Garrod, 2004; Clark & Wilkes-Gibbs, 1986). For language change to occur, speakers must first align with and then adopt new expressions into their own linguistic repertoire, spreading these through further interactions. Current studies lack direct experimentation on how alignment affects language change and often overlook real-life language phenomena like terms of address and social indexicality. This research will bridge gaps between corpus linguistics and experimental psychology, enhancing theories of alignment and language change by elucidating the linguistic, cognitive, and social mechanisms involved. Additionally, it will explore how linguistic innovations tied to social trends can spread ideas within communities, impacting various societal domains including health, education, politics, and law.