Allaité is the past participle of the verb allaiter, meaning "to breastfeed". It's an unexpected and striking word to find in a rap song, making it quite memorable.
In the lyrics, Vacra says, "C'est mon gosse, c'est moi j'l'ai allaité" (It's my kid, I breastfed him). This line is likely used metaphorically to emphasize his deep connection and responsibility to something or someone he has nurtured and brought up, perhaps referring to his music, his crew, or even his street credibility, rather than literally breastfeeding a child.
Vacra spends most of this track talking about the money, and the chorus is a shrug at the girl who wants it. "Elle aime quand j'lui paye tout, c'est une fille à papa" (She likes it when I pay for everything, she's a daddy's girl) is the whole joke: he calls her spoiled while lining up to spoil her, then admits "Mais elle a oublié que la rue ne m'oublie pas" (But she forgot that the streets don't forget me). The nickname returns as sugar in "Elle aime quand j'suis en rose comme une barbe à papa" (She likes it when I wear pink like cotton candy), because in French cotton candy is barbe à papa, literally "daddy's beard".
The verses are a victory lap with a burglar's sense of humor. He brags that "C'est pas le vent qui décoiffe, nan" (It's not the wind messing up your hair, nah) before the punchline "Nan, c'est le cabriolet" (Nah, it's the convertible), then slides into talk of locks, shutters and a Verisure alarm going off. The second verse name-checks both rappers and moves the scene to the smart Paris neighborhoods where they now have a place. Every chorus closes on the street code of "Je garde le silence, OPJ, on parle pas" (I keep quiet, cops, we don't talk), so the flashy life never quite drowns out where the money came from.