Lichenified means the skin has become thickened and leathery. This often results from continuously rubbing or scratching the skin.
Chronic irritation due to conditions such as eczema can cause lichenified skin.
Armstrong CA. Examination of the skin and approach to diagnosing skin diseases. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 444.
Habif TM. Principles of diagnosis and anatomy. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, PA: Elsevier Mosby; 2009:chap 1.