This is the 13312th most frequent Russian word.
музыкальная
Musical.
In this sentence, 'музыкальная' is used as an adjective modifying 'школа' (school), describing the type of school.
Эта музыкальная школа полна талантливых студентов.
This music school is full of talented students.
Here, 'музыкальная' describes 'мелодия' (melody), indicating that the melody is related to music.
Я слышу музыкальная мелодия, играющая на фоне.
I hear a musical melody playing in the background.
In this context, 'музыкальная' modifies 'инструмент' (instrument), signifying that the instrument is intended for producing music.