sit in on
Meaning: If you sit in on something like a meeting or a class, you attend to see what happens, without joining in.
- sit in on sth Some trainee teachers will sit in on our class today and watch what we do.
- sit in on sth Two people from Amnesty International will be sitting in on the trial.
sit in on: meeting, talks, negotiations, trial, class, lesson, session
Visitors can sit in on our meetings to