Skin infection is a broad term that encompasses a variety of conditions, including Cellulitis (10 letters), BOIL (4 letters), Staph (5 letters), and Impetigo (8 letters). Cellulitis is an infection of the deeper layers of skin and the underlying tissue, usually caused by bacteria. Boils are skin infections that start in a hair follicle or oil gland and are often caused by staph bacteria. Staph is a type of bacteria that can cause a variety of infections, including boils, impetigo, and cellulitis. Impetigo is a contagious skin infection caused by staph or strep bacteria.