For use of the term nodule in dermatology, see Cutaneous condition: Nodule In medicine nodules are solid, raised areas in or under the skin that are larger than 0.5 centimeters. Nodules may form on tendons and muscles in response to injury. The vocal cords may also develop nodules. Nodules are normally benign and often painless, although they can affect the functioning of the organ. Vocal fold nodules and thyroid nodules are examples. Furuncles and Kaposi’s sarcomae are known to cause dermatological nodules. The sexual transmitted disease (STD) gonorrhea is also known for its cause of nodules on the genitalia and mouth for those who are victim to the disease.