B1
a formal talk on a serious or specialist subject given to a group of people, especially students
Dictionary examples:
The lecture on procrastination was postponed three times. (0.0)
During the lecture on time management, half the students arrived late. (0.0)
During the lecture on concentration, most students were on their phones. (0.0)
Who's giving the lecture this afternoon? (15.0)
We went to a lecture on Italian art. (53.4)