Freio literally translates to "brake". It's an interesting word because it's used in a very idiomatic and suggestive way in this song.
Anitta sings "Hoje eu vou sentar sem freio" (Today I'm going to dance without brakes) and "Hoje ela 'tá sem freio" (Today she's without brakes). This phrase implies a complete lack of inhibition, control, or restraint, especially in a sensual and wild manner. It paints a picture of someone letting loose and not holding back, making it a memorable and enticing word in the context of the song's energetic and uninhibited vibe.
Anitta and MC Livinho's "Sem Freio" is all about letting loose and having a wild night out! The title itself, "Sem Freio," means "Without Brakes," and that's exactly the vibe they're going for. The song kicks off with Anitta mixing "tesão com álcool" [lust with alcohol] and being "no mood de dar trabalho" [in the mood to cause trouble]. It's a party anthem about hitting the club, making a scene, and not holding back.
She sings about waking up wanting to kiss someone and being ready for them to grab her, repeating "Acordei com vontade de te beijar" [I woke up wanting to kiss you]. The chorus really drives the no-holds-barred attitude home: "Hoje eu vou sentar sem freio / 'To nem aí se é pra bonito ou pra feio / O importante é quando encaixa direito" [Today I'm going to dance without brakes / I don't care if it's for pretty or ugly / The important thing is when it fits right]. It's a fun, energetic track about throwing caution to the wind and enjoying the moment, no matter what!