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frenum

or frae·num

[free-nuh m]
noun, plural fre·na [free-nuh] /ˈfri nə/. Anatomy, Zoology.
  1. a fold of membrane that checks or restrains the motion of a part, as the fold on the underside of the tongue.

Origin of frenum

< New Latin; Latin frēnum bridle
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for frena

frenum

noun plural -na (-nə)
  1. a variant spelling (esp US) of fraenum
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
frena in Medicine

frenum

[frē′nəm]
n. pl. fre•nums
  1. A membranous fold of skin or mucous membrane that supports or restricts the movement of a part or organ, such as the small band of tissue connecting the tongue to the floor of the mouth.
  2. An anatomical structure resembling such a fold.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.