Manantial literally translates to "spring" or "fountain" (as in a natural water source). It's a beautiful and evocative word that isn't heard in every song.
In "Manantial De Amor," the singer uses it as a metaphor to describe his beloved as a "spring of love" (manantial de amor). He wants to "drink a little from her," implying that her love is a refreshing and endless source of joy and affection. This poetic imagery makes the word particularly memorable and enticing.
"Manantial De Amor" ("Spring of Love") is a classic Colombian vallenato love song from Binomio de Oro de América. The singer describes the wonder of meeting someone who instantly feels familiar, as if he had known her forever.
He compares her beauty to flowers like the camellia, the rose and the carnation, and admits he can't find the words to express what he feels. Losing sleep thinking about her love, he calls her his "manantial de amor" — a spring, or wellspring, of love — and asks only to be allowed to drink from that love and give her his whole heart in return.
By the end, he pictures her as the moon that lights up his love, while he is the humble sparrow ("pobre gorrión") who sings from the soul, hopelessly in love. It's a warm, devoted declaration typical of the genre — sincere rather than showy, and centered on gratitude for having found her.