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spirometer

[spahy-rom-i-ter]
noun
  1. an instrument for determining the capacity of the lungs.

Origin of spirometer

First recorded in 1840–50; spiro-1 + -meter
Related formsspi·ro·met·ric [spahy-ruh-me-trik] /ˌspaɪ rəˈmɛ trɪk/, spi·ro·met·ri·cal, adjectivespi·rom·e·try, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for spirometry

spirometer

noun
  1. an instrument for measuring the air capacity of the lungsCompare pneumatometer
Derived Formsspirometric (ˌspaɪrəˈmɛtrɪk), adjectivespirometry, noun
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 spirometry

spirometer

n.

1846, formed irregularly from Latin spirare "to breathe" (see spirit (n.)) + -meter. Related: Spirometry.

Online Etymology Dictionary, © 2010 Douglas Harper
spirometry in Medicine

spirometer

[spī-rŏm′ĭ-tər]
n.
  1. An instrument for measuring the volume of air entering and leaving the lungs.
Related formsspi′ro•met′ric (-rə-mĕt′rĭk) adj.spi•rom′e•try n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.