Cat
Have you a picture of the cat you can post here? "Limps" helps a bit as does "tuxedo" but this description could fit a number of cats in the area. A picture of the cat would help those who want to help in the search identify whether a cat they may see in their yard is the cat referred to in your OP.
Is the cat chipped with current residence information or wearing a cat license or other identifying tag on their collar? If not, you may need to contact/visit AHS in Newark since that is where an unidentifiable cat may have been taken if found.
Are you sure the cat got our of the house? Cats have been known to sleep/hide/get accidentally enclosed in the least likely places. Have you done a thorough search - drawers, closets, inside recliners, even in walls? Did someone actually see the cat exit the house?
If this is an indoor cat who is outside, the cat is likely in an enclosed space near by. Check your [and ask neighbors to check their] garage, crawl space(s), sheds, thick brush, or any other space the cat may have gotten into.
Lost, 5/30/15 Tuxedo rescue House Cat, 13 yrs old. Colgate Rd. Maplewood. History of damaged back legs, limps. 973-763-6324. Thanks