nuclear magnetic resonance

American  

[noo-klee-er mag-net-ik rez-uh-nuhns, nyoo-] / ˈnu kli ər mægˈnɛt ɪk ˈrɛz ə nəns, ˈnyu- /

noun

Physics.

1. the selective absorption of electromagnetic radiation by an atomic nucleus in the presence of a strong, static, magnetic field: used in research and in medicine to monitor tissue metabolism and to distinguish between normal and abnormal cells. NMR

---

nuclear magnetic resonance British  

noun

1.  NMR.  a technique for determining the magnetic moments of nuclei by subjecting a substance to high-frequency radiation and a large magnetic field. The technique is used as a method of determining structure See also electron spin resonance

---

nuclear magnetic resonance Scientific  

1. The absorption of electromagnetic energy (typically radio waves) by the nuclei of atoms placed in a strong magnetic field. The nuclei of different atoms absorb unique frequencies of radiation depending on their environment, thus by observing which frequencies are absorbed by a sample placed in a strong magnetic field (and later emitted again, when the magnetic field is removed), it is possible to learn much about the sample's makeup and structure. Nuclear magnetic resonance has no known side effects on the human body, and is therefore used to analyze soft body tissues in magnetic resonance imaging (MRI).

---

Pronunciation

See nuclear ( def. ).

Etymology

Origin of nuclear magnetic resonance

First recorded in 1940–45

Example Sentences

The physics of nuclear magnetic resonance had been a laboratory tool since the 1940s, but it took Raymond Damadian’s 1977 breakthrough to produce the first human scan.

From The Wall Street Journal • Apr. 24, 2026

With this protection, the carbene becomes stable enough for detailed analysis using nuclear magnetic resonance spectroscopy and x-ray crystallography, offering clear evidence that such molecules can exist in water.

From Science Daily • Apr. 11, 2026

Moreover, other options, such as nuclear magnetic resonance spectroscopy, required cutting large parts of the protein or chemically manipulating it in a way that would transform its physiological state and potentially alter its function.

From Salon • Dec. 13, 2022

At UPR, scientists who use a nuclear magnetic resonance spectrometer for their work have had to use flashlights as they pour the liquid nitrogen needed to maintain the instrument.

From Science Magazine • Sep. 27, 2022

It took 18 months to build the first M.R.I., originally known as a nuclear magnetic resonance scanner, or N.M.R.

From New York Times • Aug. 17, 2022