A herniated disc may be caused by: 1  Wear and tear of the disc. As you age, your discs dry out and aren't as flexible. 2  Injury to the spine. This may cause tiny tears or cracks in the hard outer layer of the disc.
Definition of wart. 1a : a horny projection on the skin usually of the extremities produced by proliferation of the skin papillae and caused by any of numerous human papillomaviruses âcalled also verruca vulgarisb : any of numerous similar skin lesions not caused by viruses.
This topic has information about warts on any part of the body except the genitals. For information about warts on the genitals, see the topic Genital Warts. A wart is a skin growth caused by some types of the virus called the human papillomavirus (HPV). HPV infects the top layer of skin, usually entering the body in an area of broken skin. The virus causes the top layer of skin to grow rapidly, forming a wart. Most warts go away on their own within months or years.