Noremac

Mexican is a nationality, not a race.

Have you heard of Cockney rhyming slang? Take a word like “fart”, use a two part word that rhymes with it, like “raspberry tart”, then drop the rhyming part. That leaves you with “raspberry” meaning “fart” and no discernible connection to the old words this utterance/meaning pair came from.

So that’s where “blowing raspberries” came from? Pretty neat.