The Vietnamese word "diễn giảng" means "to lecture" or "to give a lecture." It refers to the act of presenting information or teaching a subject, often in a formal setting, like a classroom or seminar.
In more advanced contexts, "diễn giảng" can also imply a more interactive discussion rather than just a one-sided presentation. It can involve engaging students or listeners in discussions or questions related to the topic being lectured on.