a premalignant warty lesion occurring on the sun-exposed skin of the face or hands in aged light-skinned persons; hyperkeratosis may form a cutaneous horn, and squamous cell carcinoma of low-grade malignancy may develop in a small proportion of untreated patients. Syn: senile keratoderma, senile keratoma, senile keratosis, keratosis senilis, senile wart, solar keratosis, verruca plana senilis, verruca senilis.