Profane language is the kind that gets bleeped on TV. The word profane can also describe behavior that's deeply offensive because it shows a lack of respect, especially for someone's religious beliefs.
The Latin root profanus means "unholy," and that's where it all started. If you take the Lord's name in vain, you've profaned Him and probably made your religious mom pretty angry too. Don't even try the profane curse words so vital to a truly great hip-hop track but perhaps not recommended for dinner with Grandma.