Lenha translates to "firewood". It's an interesting word because it's not commonly found in everyday song lyrics, making it stand out.
In the context of the song, the phrase "Você traz a lenha pro meu fogo acender" (You bring the firewood for my fire to light) uses "lenha" metaphorically. It implies that the person brings what is needed to ignite passion or keep a relationship burning, adding a poetic and evocative layer to the lyrics.
"Lenha" opens with Rionegro & Solimões admitting they can't get their own signals straight. "Eu não sei dizer, o que quer dizer, o que eu vou dizer" [I don't know how to say, what it means, what I'm going to say] is the very first line, and it sets the tone: this isn't a love song built on certainty. "Eu amo você, mas não sei o que isso quer dizer" [I love you, but I don't know what that means] follows right after, and it reads less like romance than an honest shrug.
The chorus turns that confusion into instructions the other person has to read on the fly. "Se eu digo pare" [If I say stop] pairs with "Você não repare no que possa parecer" [Don't mind what it might seem like], and "Se eu digo siga" [If I say go] pairs with "Você não vai entender" [You won't understand]. Whatever he says out loud, don't trust it. Only one line comes through clean: "Você traz a lenha pro meu fogo acender" [You bring the firewood to light my fire]. Say "come," and she already knows what to do with it. The wood is the one thing he can actually put into words.