There has been little research on academic writers that shows how social interaction influences the construction of "discoursal identity" (the impressions that writers convey about themselves in their texts and that readers develop about writers). This study analyzes a collaborative writing session among college students to explore the negotiation of discoursal identity in the selection of a single word, "discourse". Drawing on video-based conversation analysis and ethnographic methods, it argues that the writers' embodied stances on the word "discourse" index an array of identities: that of the teacher and class (over)using the word, the teacher reading the word, the good student who fluently uses the word, the student who displays that the word is not a natural part of her vocabulary, and the student who is trying not to "show off." Through an examination of stancetaking during group work and interviews, this study details how interaction constructs discoursal identities. (Contains 1 table and 4 figures.)