Giant enterocystoma within an infant's tongue. A rare developmental cyst within the tongue and submandibular triangle of a male infant containing heterotopic gastric and intestinal epithelium (enterocystoma) is described and its derivation discussed. This cyst was of such a size as to cause feeding difficulties and partial airway obstruction during sleep. Following C.T. scanning, total obstruction necessitated an emergency tracheostomy. Successful enucleation via a median labiomandibulotomy was performed without further complication and two years later there is no sign of recurrence. 