Ankyloglossia
A minor congenital anomaly (birth defect) in which the flap of mucous membrane under the tongue (known as the frenum) is too short and limits the normal mobility of the tongue.
Ankyloglossia is also called tongue tie from the folk belief that the anomaly causes feeding and speech problems.
A child cannot feed or speak properly because their tongue is 'tied.' This belief is popular but unfounded.