Blockage along the course of the minor salivary duct which causes pooling of saliva behind the obstruction and localized swelling, is known as:
In the retention mucocele, there is a blockage along the course of the minor salivary duct which causes pooling of saliva behind the obstruction and localized swelling. This pooling of saliva causes a  pressure build-up and dilates the duct of the minor salivary gland. This dilated ductal epithelium forms a lining around the saliva and mimics a cyst-like lesion.
Ranula is the clinical term for a mucocele occurring on the floor of the mouth after trauma to components of the sublingual glands. Two varieties of ranula exist: cystic (mucus retention cyst) and pseudocystic (mucus retention phenomenon or mucocele). In the cystic type, there is partial obstruction of the distal end of a sublingual gland duct that results in a small epithelial lined cyst usually less than 1 cm in diameter. However, the pseudocystic type, which is more common, forms as a result of extravasation of mucus into the fibrous connective tissue after a tear in a sublingual gland duct and, as in the case of a mucocele, arises as a result of the escape of mucus into the adjacent connective tissue. The clinical term 'plunging ranula' is used when extravasated mucus dissects through the mylohyoid muscle and along the fascial planes of the neck, producing a swelling evident in the floor of the mouth. 
Key concept:
Ranula is specifically for this mucocele occurring on the floor of the mouth after trauma to components of the sublingual glands.
John S. McDonald, in McDonald and Avery's Dentistry for the Child and Adolescent (Tenth Edition), 2016
Ranula
Retention mucocele
Mucous extravasation mucocele
Sialolithiasis