Trauma: This is the most common cause of a cut on the tongue, often resulting from accidental biting during eating, speaking, or other oral activities. The history and physical examination usually support this diagnosis.

Aphthous ulcers: Although these are more commonly found on the inside of the cheeks, lips, or at the base of the gums, they can occasionally appear on the tongue. They are usually painful and can be triggered by stress, minor mouth injury, or certain foods.
Oral lichen planus: This chronic inflammatory condition can affect the mucous membranes inside the mouth, including the tongue. It may cause lesions that could be mistaken for cuts.
Allergic reactions or irritations: Certain foods, substances, or oral care products can cause an allergic reaction or irritation, leading to lesions or cuts on the tongue.

Squamous cell carcinoma: Although rare, any unexplained or persistent lesion on the tongue should raise suspicion for oral cancer, especially in individuals with risk factors such as tobacco use or excessive alcohol consumption.
Infections (e.g., herpes simplex, syphilis): Certain infections can cause ulcers or lesions on the tongue that might be mistaken for cuts. These conditions require prompt diagnosis and treatment.
Autoimmune disorders (e.g., pemphigus): These are rare conditions that can cause blistering of the skin and mucous membranes, including the tongue.

Eosinophilic ulcers: These are rare and can appear on the tongue, often associated with eosinophilia or as part of an allergic reaction.
Granulomatosis with polyangiitis (formerly known as Wegener's granulomatosis): A rare autoimmune disorder that can affect various parts of the body, including the mouth, and cause ulcers or lesions.
Behçet's disease: A form of vasculitis that can cause a wide range of symptoms, including oral ulcers that might appear on the tongue.