Definition of “series” - Learner’s Dictionary

series

noun [ C ] us uk /ˈsɪəriːz/ plural series
This is the latest in a series of terrorist attacks in the region.They suffered a series of mishaps during the trip.I've started the ball rolling by setting up a series of meetings.The course culminates in a series of written exams.A series of scandals have undermined people's confidence in the government.
SAME THINGS

B2 several things or events of the same type that come one after the other:

a series of lectures
TELEVISION/RADIO

B1 a group of television or radio programmes that have the same main characters or deal with the same subject:

a four-part drama series

(Definition of “series” from the Cambridge Learner's Dictionary © Cambridge University Press)