Suspirando comes from the verb suspirar, meaning "to sigh." While a sigh can sometimes indicate sadness, in this song, it carries a more romantic connotation of longing or yearning.
The lyrics mention "Por lo que suspirando" (For which I am sighing/longing), suggesting a deep desire and anticipation for the "par de ojitos negros" (pair of dark eyes). It's a poetic way to express a profound emotional connection and yearning for someone.
This song is all about a guy who is completely smitten by a pair of dark eyes. He says, "por un par de ojitos negros anda mi amor navegando" [for a pair of dark eyes my love is sailing], meaning his whole world, his love, is just floating around because of these eyes. He's so focused on them, he even says he lives waiting for them, "por ello vivo esperando." He thinks they're so beautiful, "qué bonito para de ojitos" [what a beautiful pair of eyes]!
It gets a little intense because he's heard that these eyes have been seen around, and he's determined to find them. He even says, "si hay uno que los quieran que me los venga quintás y traigo pistola en el cinto por si quiere reclamar" [if there's someone who wants them, let them come take them from me, and I have a pistol on my belt in case they want to claim them]. Wow! He's ready to fight for this person! He's going to prove his love and take her with him. It's a pretty bold declaration of love and desire, all for those beautiful dark eyes.