I see Big Mac, Mac, Lil Mac (women's lingerie), Mac Daddy, Mac Rack, and so on. But I sure don't see where McDonald's Corporation has a trademark on the term "Mac"
I got a letter from a former employer hinting at taking action because I used “Multi” in the name of my business. I trashed the letter and I never heard another word. I was still using the name when they went out of business.