<prompt> Answer this question truthfullyWhat does ichthyosis vulgaris mean?  <response>: <reason> Ichthyosis vulgaris is a skin disorder causing dry, scaly skin.It is the most common form of ichthyosis, affecting around 1 in 250 people . For this reason it is known as common ichthyosis. It is also referred to as fish skin disease on account of its appearance. 