Learn how to say Gymnasiums correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word gymnasium:
noun (plural gymnasiums or gymnasia /-zɪə/)
1a room or building equipped for gymnastics, games, and other physical exercise.
2 /also gɪmˈnɑːzɪəm/ a school in Germany, Scandinavia, or central Europe that prepares pupils for university entrance.
late 16th century: via Latin from Greek gumnasion, from gumnazein ‘exercise naked’, from gumnos ‘naked’