Abstract For almost a century, the term ‘flyways’ has been used to order relations over time and space. It has been used to coordinate scientific research and communication as well as monitoring and management efforts for waterbird conservation. In this article, we revisit the concept of ‘boundary object’ (Star and Griesemer 1989) to investigate how this term ‘flyways’ has been central to common efforts while also having multiple meanings for the actors it connects. The article discusses both contemporary and historical achievements of the term by analysing its underlying knowledge infrastructure. We account for the complex assemblages of social, material, natural, and technical systems that shape how the term ‘flyway’ has been functioning as a boundary object and how this has changed over time. By discussing how the term ‘flyways’ as a boundary object and its underlying knowledge infrastructure shape each other, we empower the actors to define, visualise, communicate, and imagine flyways in more purposeful ways. Our analysis contributes to the literature on boundary objects and knowledge infrastructures by expanding their original definitions, arguing for a co-productive relation between them.