register with (someone or something)
1. To give one's name or other details with a particular person, place, department, organization, etc. You'll need to register with someone at the front desk before you can come into the building. Be sure to register with Citizenship and Immigration Services as soon as you arrive in the country.
2. To give someone's, something's, or one's own name or other details with a particular person, place, department, organization, etc. In this usage, a noun or pronoun is used between "register" and "with." We need to register the business with the appropriate tax authority. I homeschool my children, but I still need to register them with the local school district. By registering your product with the manufacturer, you are guaranteed a minimum warranty under EU law.
3. To be understood or comprehended by someone; to make an impression or have an effect on someone. I could tell that the news of her son's death was not registering with her. I showed the victim several pictures of possible suspects, but none of them registered with him.
register something with someone or something
to record the existence of something with someone or something. Did you register your new stereo with the manufacturer? If you bring any packages into this store, please register them with the manager.
register with someone
1. Lit. to sign up with someone. You will have to register with the lady at the front desk. I registered with the attendant when I came in.
2. Fig. [for something] to be realized or understood by someone. Suddenly, the import of what she had said registered with me. My name did not register with her, and I had to explain who I was.