Bangor University has confirmed it will close its chemistry department and jobs will also be lost in other departments.
The university, among the oldest in Wales, blamed financial pressures, competition and falling students numbers for the cuts.
Up to 60 jobs were under threat after the university announced in October it had to cut £5m.
Bangor was the only university offering people the chance to study chemistry in Welsh.
There will also be job losses in both finance and corporate services as well as in the schools of Education and Human Development, Medical Sciences, Health Sciences, and Sport, Health and Exercise Sciences.
Students held protests against the proposed cuts during a three-month consultation process.