Desilusão translates to "disillusionment" or "disappointment". It's a strong emotional word that conveys a sense of lost hope or shattered expectations.
In the song, the singer expresses a deep fear of being hurt again, stating, "Já sofri, já chorei desilusão" (I've already suffered, I've already cried disillusionment). This word perfectly encapsulates the pain of past heartbreaks and the emotional guard the singer has put up, making it a poignant and relatable term for anyone who has experienced romantic disappointment.
"Se Não For Por Amor" ("If It's Not For Love") is Amado Batista singing to someone who is getting close to him, and warning them not to unless they mean it.
He opens by saying he doesn't want to fool himself again or get hurt again. He's been burned before, and he's scared of falling for another illusion. So he asks the other person to stop looking at him that way, to stop playing games, because he knows he'll give in if they keep pushing.
The chorus is the heart of the song: if it's not for love, don't try to seduce him. He admits he's weak, that he won't be able to resist, and that the other person is "too much" for him to hold out against. But if they tell him it really is love, he'll love them back completely.
It's a song about wanting real love badly enough to guard against anything less, even while knowing how easy it would be to give in anyway.