Aplaudir means "to applaud" or "to clap". It's an interesting verb that isn't as common in everyday conversation or song lyrics as more basic verbs.
In the context of "Reggae Bom", the line "Ninguém veio aqui pra te aplaudir" (Nobody came here to applaud you) sets a tone of authenticity and self-reliance. It suggests that one shouldn't seek external validation, but rather live for themselves, making it a thought-provoking word choice.
Lagum's "Reggae Bom" opens with permission, not pressure: "Você não precisa fazer o que não quiser" [You don't need to do what you don't want]. Nobody in the room came to judge; "Ninguém veio aqui pra te aplaudir" [Nobody came here to applaud you] means exactly that. So the singer refuses a stranger's stare: "Não me olhe com esses olhos, de quem nunca me viu antes" [Don't look at me with those eyes, of someone who never saw me before].
The chorus turns that scene into a plea to stay. "Diz que vai voltar, traz contigo aquele reggae bom" [Say you'll come back, bring that good reggae with you] asks for the person, and the mood, to return together. Whatever doubt kept someone at the door, the answer is patience rather than a chase: "Mas não vou ficar parado, amor, esperando 'cê chegar" [But I won't stand still, love, waiting for you to arrive].