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fraenum

American  
[free-nuhm] / ˈfri nəm /

noun

Chiefly British.

plural

fraena
  1. a variant of frenum.


fraenum British  
/ ˈfriːnəm /

noun

  1. a fold of membrane or skin, such as the fold beneath the tongue, that supports an organ

"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

Etymology

Origin of fraenum

C18: from Latin: bridle