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olfaction

[ol-fak-shuh n, ohl-]
noun
  1. the act of smelling.
  2. the sense of smell.

Origin of olfaction

1840–50; < Latin olfact(us) past participle of olfacere to smell (see olfactory) + -ion
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for olfaction

olfaction

noun
  1. the sense of smell
  2. the act or function of smelling
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 olfaction
n.

noun of action from Latin olfactus, past participle of olfacere "to smell, get the smell of" (transitive), from olere "to emit a smell" (see odor) + facere "to make" (see factitious).

Online Etymology Dictionary, © 2010 Douglas Harper
olfaction in Medicine

olfaction

[ŏl-făk′shən, ōl-]
n.
  1. The sense of smell.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.