tonometer

1 of 2

noun (1)

to·​nom·​e·​ter tō-ˈnä-mə-tər How to pronounce tonometer (audio)
1
: an instrument or device for determining the exact pitch or the vibration rate of tones
2
: an instrument for measuring tension or pressure and especially intraocular pressure
tonometry
tō-ˈnä-mə-trē How to pronounce tonometer (audio)
noun

tonometry

2 of 2

noun (2)

to·​nom·​e·​try tōˈnämə‧trē How to pronounce tonometry (audio)
plural -es
: the act or practice of measuring with a tonometer

Examples of tonometer in a Sentence

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Noun
Eye doctors today measure this intraocular pressure using a tonometer, but the test is not always accurate. — IEEE Spectrum, 24 Aug. 2014 While Morgan was wearing the Chibis pants, Meir used a tonometer to measure his eye pressure, with doctors on Earth watching in real time. — Ashley Strickland, CNN, 23 Mar. 2020

Word History

Etymology

Noun (1)

Greek tonos tone + English -meter

Noun (2)

International Scientific Vocabulary tono- + -metry

First Known Use

Noun (1)

1725, in the meaning defined at sense 1

Time Traveler
The first known use of tonometer was in 1725

Rhymes for tonometer

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Browse Nearby Words

tonology
tonometer
tonometric
See all Nearby Words

Cite this Entry

“Tonometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tonometer. Accessed 8 Jul. 2026.

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Medical Definition

tonometer

noun
to·​nom·​e·​ter tō-ˈnäm-ət-ər How to pronounce tonometer (audio)
: an instrument for measuring tension or pressure and especially intraocular pressure
tonometric
ˈtō-nə-ˈme-trik How to pronounce tonometer (audio) ˌtän-ə- How to pronounce tonometer (audio)
adjective
tonometry
tō-ˈnäm-ə-trē How to pronounce tonometer (audio)
noun
plural tonometries

More from Merriam-Webster on tonometer

Britannica.com: Encyclopedia article about tonometer

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