webinar UK /ˈwɛb.əˌnɑː/US /ˈwɛb.əˌnɑɹ/ noun1 •An interactive seminar conducted via Internet. Usually a live presentation, lecture or workshop that happens in real time, as users participate through text-based chat, voice, video, or file-sharing.I just got an email invitation to a webinar on the value of primary sources. formsWebinars · webinars