Contextual elaborations and shifts when adult L2 learners present and discuss workplace-related vocabulary

•Placement-related words were negotiated multicontextually and collaboratively.•The teacher explicitly pointed out differences in contextual meaning.•The student contributed questions, specialized expressions and personal experiences.•Placement experiences provided context-specific meaning and scaffolding.•The study develops the concepts of contextual elaboration and shifts. This study aims to contribute knowledge about how the meanings of words selected by students based on workplace experiences (placements) in basic adult L2 education were negotiated in classroom discourse. The study, conducted in the context of Swedish for Immigrants (SFI), drew inspiration from practice-based and ethnographic methodology. It focuses on a vocabulary assignment connected to students’ placements at preschools and a hotel. The analysis was based on transcribed audio recordings and underpinned by the theoretical perspective of knowledge-building interaction. As a theoretical contribution to the field, the study develops the concepts of contextual elaboration and shifts. The findings show that some students successfully used placement experiences to contextualize their chosen words, while others found it challenging to contextualize abstract words. In the follow-up discussions, the teacher, and the students collaboratively and multi-contextually expanded on word meanings by exploring different collocations and contexts of use.