Cinturita is the diminutive form of cintura (waist), literally meaning "little waist." This word is endearing and highlights a specific physical attribute in a charming way.
In the song, the lyrics
Get ready to dance with Los Hermanos Rosario's "Morena Ven"! This song is a pure celebration of love and attraction, Dominican style. The singer is completely smitten, declaring, "la quiero tanto esa mujer la quiero tanto" [I love her so much, I love that woman so much]. He finds her absolutely beautiful, exclaiming "es hermosa eso me encantó es hermosa" [she is beautiful, that enchanted me, she is beautiful].
He's so captivated by this "morena" [dark-haired woman] that he can't even think about leaving. He's determined to stay and pursue her, saying, "no me voy aquí yo vine agujas mire esa muchacha ay qué bueno está no me voy a ir a buscarla" [I'm not leaving, I came here, look at that girl, oh how good she is, I'm not going to leave to look for her]. He's mesmerized by her figure, describing her "cinturita" [little waist] as if she's a "muñequita" [little doll]. It's a fun, energetic track about falling head over heels and not being afraid to show it!