Situated at the center of public scientific discourse are specific scientific objects, about which even a layperson could have some vague idea. These objects have been theoretically described in science and technology studies by Star and Griesemer (1989:393) as the boundary objects that “are both plastic enough to adapt to local needs and the constraints of several parties employing them, yet robust enough to maintain a common identity across sites”. Nevertheless, systematic descriptions of boundary objects that facilitate public communication of science and technology are few and far between.

This study attempts to provide the description of GMO (genetically modified organism) as an exemplar case of a kind of boundary object from the perspective of Systemic Functional Linguistics (SFL), which has developed as an appliable kind of linguistics characterized by its “social accountability” (Halliday 1975/2003), forging dialogue between theory building and its applications.

The methodology proposed to describe the boundary object is carried out on a piece of New York Times’ feature science story together with readers’ comments marked by the newspaper as NYT Picks. SFL’s cline of stratification is explored to examine how the boundary object GMO construed in the text is essentially a semiotic object characterized by “metaredundancy” within its subsystems. The boundary object is first of all construed by a kind of generic hybridity. This is in turn realized by contextual parameters, particularly that of field which is linked to GMO-related activities and that of tenor which is linked to GMO-related voices and opinions. By drawing on the experiential (the TRANSITIVITY system) and the interpersonal meaning resources (internal/external parameters of evaluation remodeled upon the appraisal framework), the study sheds light on the linguistic properties of the boundary object.

Meanwhile, social accountability also engages SFL in trans-disciplinary dialogue with Legitimation Code Theory (LCT; e.g. see Maton 2014) developed upon Bernstein’s account on knowledge structures. The dialogue is in a position to recontextualize linguistic properties of the boundary object within LCT’s knowledge-knower structure, which generates greater explanatory power.

The study reveals that the emergent boundariness of the boundary object is construed respectively by the generic, the experiential, and the evaluative boundaries, and these boundaries eventually culminates in the epistemic-social ones leading to a “hierarchical knower structure” in the public scientific text. Descriptions of the boundary object presented in the study will make this relatively abstract sociological notion more accessible, and contribute to functional-semantic approaches to human-object relationships.