Ranula: A type of mucocele that occurs on the floor of the mouth, typically resulting from the obstruction of the sublingual gland or duct. It is the most common cause of swelling in this area, especially in young individuals.

Mucocele: Similar to a ranula but can occur in other parts of the mouth due to the obstruction of minor salivary glands. It presents as a soft, painless, and translucent swelling.
Ludwig's Angina: A severe infection of the submandibular space that can cause swelling and pain in the floor of the mouth. It's a significant condition due to potential airway compromise.
Sublingual Abscess: An accumulation of pus under the tongue, which can cause swelling, pain, and difficulty speaking or swallowing.
Sialadenitis: Inflammation of the salivary glands, which can cause swelling and pain, particularly if the sublingual or submandibular gland is involved.

Oral Cancer: Although less common, swelling at the floor of the mouth could be a sign of oral cancer, particularly if there's a history of tobacco or alcohol use. Early detection is crucial for treatment outcomes.
Deep Neck Infection: Infections in the deep spaces of the neck can spread to the floor of the mouth, causing swelling. These infections can be life-threatening due to the risk of airway obstruction.
Angioedema: A condition characterized by rapid swelling of the dermis, subcutaneous tissue, mucosa, and submucosal tissues. It can be life-threatening if it involves the airway.

Cystic Hygroma: A congenital condition that can present as a soft, cystic swelling in the neck or floor of the mouth, typically noticed at birth or during infancy.
Teratoma: A type of tumor that can occur in the mouth, including the floor, and is typically present at birth.
Lymphangioma: A rare, benign tumor of the lymphatic vessels that can cause swelling in various parts of the body, including the floor of the mouth.