Tilde translates to 'accent mark', but unlike in English where it usually refers to the wavy line over an 'n' (ñ), in Spanish it means the written accent mark (´) that gives a syllable its emphasis.
Sebastián Yatra uses this grammatical term in a clever, poetic way when he sings, "Tú le pones la tilde a mi corazón" (You put the accent mark on my heart). This beautiful metaphor implies that his partner gives his heart the perfect emphasis and makes it completely whole, making it an unforgettable phrase for language learners.
This song is a total celebration of a partner with what Sebastián Yatra calls “una energía que está bacana” (an energy that's cool). He's not singing about someone who saved him from a bad place; instead, he makes it clear that “Ya todo estaba bien / Y ahora estoy mejor” (Everything was already good / And now I'm better). She's the upgrade to his already happy life.
He lists all the ways she makes him feel amazing. She relaxes him “como una cerveza” (like a beer) and makes him feel high even though he says “Nunca fumé marihuana” (I never smoked marijuana). The song is full of sweet and specific compliments, like how she “le pones el sábado a mi semana” (you put the Saturday in my week) and “le pones la tilde a mi corazón” (you put the accent mark on my heart). It's a picture of a relationship built on a great foundation, where he was her “pana” (buddy) before becoming her boyfriend, and their connection is all about “Cero drama, cero estrés” (Zero drama, zero stress).