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nasal index

noun
  1. Craniometry. (of the skull) the ratio of the distance from nasion to the lower margin of the nasal aperture to that of the maximum breadth of the nasal aperture.
  2. Cephalometry. (of the head) the ratio of the maximum breadth of the external nose to its height from the nasal root to where the septum is confluent with the upper lip.

Origin of nasal index

First recorded in 1895–1900
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for nasal index

nasal index

noun
  1. the ratio of the widest part of the nose to its length multiplied by 100
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