Sacanagens is a plural noun derived from sacanagem, which translates to "mischief," "dirty tricks," or even "naughtiness."
In the context of the song, it suggests a playful yet cunning attitude, implying someone who is skilled in outsmarting others or engaging in clever antics. It's an interesting word because it captures a specific kind of mischievous behavior that isn't always directly translatable with a single English word, making it memorable and engaging for learners.
In "Troquei de Mina," which translates to "I Changed My Girl," the singer presents himself as a player who can't be fooled. He boasts that he's "graduated in mischief" (graduado em sacanagens) and knows how to take care of himself, so no one should think they can deceive him.
The central theme is his casual attitude towards relationships. He declares that he changes women as easily as he changes clothes. The lyrics describe new girlfriends appearing, including one who is eighteen, and his choice to throw himself into the late-night party scene (me jogar nas madrugadas). It's a song about a carefree, perhaps reckless, lifestyle focused on moving from one romance to the next without getting too attached.