The phrase comes from Brazilian Portuguese internet humour, where a speaker gives up trying to define something and settles for calling it a thing of I do not know what. Its published soundboard listing associates the clip with Garras da Patrulha, and that connection has helped it circulate among Portuguese-speaking meme pages and short-form editors. It remains popular because the wording is flexible: it fits almost any unclear situation without needing context, translation or a setup, so creators keep reusing it as a quick, instantly understood reaction to confusion.