This is the 6271st most frequent Dutch word.
spaanse
"Spaanse" means "Spanish" (adjective, feminine or plural form in Dutch).
In this sentence, 'Spaanse' is used as an adjective to describe 'leraar' (teacher), specifying the origin or specialty of the teacher being Spanish.
Mijn vriendin heeft een Spaanse leraar.
My friend has a Spanish teacher.
Here, 'Spaanse' is acting as an adjective modifying 'muziek' (music), indicating the type or style of music as Spanish.
Ik hou erg van Spaanse muziek.
I really love Spanish music.
In this instance, 'Spaanse' describes 'gerechten' (dishes), designating the cuisine or preparation style of the food being Spanish.