impedance

noun

im·​ped·​ance im-ˈpē-dᵊn(t)s How to pronounce impedance (audio)
: something that impedes : hindrance: such as
a
: the apparent opposition in an electrical circuit to the flow of an alternating current that is analogous to the actual electrical resistance to a direct current and that is the ratio of effective electromotive force to the effective current
b
: the ratio of the pressure to the volume displacement at a given surface in a sound-transmitting medium

Examples of impedance in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
There is a dedicated, high-impedance guitar/bass input as well as two stereo ¼-inch inputs for keyboards or electronic drums. — Mark Sparrow, Forbes.com, 21 June 2026 That's why speakers with lower impedance, rated in ohms, can generally be more difficult to amplify. — Ryan Waniata, Wired News, 1 Apr. 2026 This layout fundamentally shifts the way at-home bioelectrical impedance works. — New Atlas, 1 July 2026 In addition, the length will, in part, determine the necessary impedance, or maximum ohm load and resistance of a speaker cable. — Bestreviews, Mercury News, 9 Jan. 2026 See All Example Sentences for impedance

Word History

First Known Use

1886, in the meaning defined above

Time Traveler
The first known use of impedance was in 1886

Rhymes for impedance

See All Rhymes for impedance

Browse Nearby Words

impecunity
impedance
impedance bond
See all Nearby Words

Cite this Entry

“Impedance.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impedance. Accessed 7 Jul. 2026.

Copy Citation

Medical Definition

impedance

noun
im·​ped·​ance im-ˈpēd-ᵊn(t)s How to pronounce impedance (audio)
1
: the apparent opposition in an electrical circuit to the flow of an alternating current that is analogous to the actual electrical resistance to a direct current and that is the ratio of effective electromotive force to the effective current
2
: the ratio of the pressure to the volume displacement at a given surface in a sound-transmitting medium
3
: opposition to blood flow in the circulatory system

More from Merriam-Webster on impedance

Britannica.com: Encyclopedia article about impedance

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