The crossword solutions for the term SMALL OR CHICKEN are POX. POX is a general term used to describe a number of viral diseases, including chickenpox and smallpox. Chickenpox is an infectious disease caused by the varicella-zoster virus, which is characterized by itchy blisters on the skin. Smallpox is a highly contagious and potentially fatal disease caused by the variola virus. It is marked by fever and a distinctive, progressive skin rash.