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philtrum

[fil-truh m]
noun, plural phil·tra [fil-truh] /ˈfɪl trə/.
  1. Anatomy. the vertical groove on the surface of the upper lip, below the septum of the nose.
  2. a philter.

Origin of philtrum

1600–10; < Latin: love philter < Greek phíltron love philter, dimple in upper lip. See phil-, -tron
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for philtrum

philtrum

noun plural philtra
  1. the indentation above the upper lip

Word Origin for philtrum

C17: from Latin, see philtre
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
Word Origin and History for philtrum
n.

dimple in the middle of the upper lip, 1703, medical Latin, from Greek philtron, literally "love charm" (see philtre).

Online Etymology Dictionary, © 2010 Douglas Harper
philtrum in Medicine

philtrum

[fĭl′trəm]
n. pl. phil•tra (-trə)
  1. The vertical indentation in the midline of the upper lip.infranasal depression
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.