HP_0002745 (Oral leukoplakia) is a thickened white patch on the oral mucosa that cannot be rubbed off. Also known as: Oral idiopathic keratosis, Oral idiopathic leukoplakia, Oral idiopathic white patch, Oral leucoplakia, Oral leukokeratosis, Oral leukoplasia, Oral white patch, Oral white plaque.