The definition of a frenum is a fold of skin or a mucous membrane that limits or controls the movement of an organ or body part.(noun)
The small piece of pink skin that attaches the tongue to the bottom of the mouth is an example of a frenum.
See frenum in Webster's New World College Dictionary
See frenum in American Heritage Dictionary 4
noun pl. fre·nums or fre·na (-nə)
Origin: Latin frēnum, bridle
Origin: , from frendere, to grind; see ghrendh- in Indo-European roots.
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