Precancerous condition in case of carcinoma of oral cavity is known as :

Oral leukoplakia—a persistent white patch or plaque on the oral mucosa that cannot be scraped off and is often associated with tobacco or betel quid use—is a well-recognized precancerous (potentially malignant) lesion that can progress to squamous cell carcinoma of the oral cavity. Aphthous ulcers, simple hyperplasia, and hypertrophy are benign conditions.