Extremely fine, especially of the hyperfine structure in the spectra of atoms and molecules.(adjective)
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Use "hyperfine" in a sentence
"The magnetic field separates these levels into two "hyperfine" states."
"Have you a device by which I might measure the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom?"
"They feature a picture of the solar system, a picture of the probes and a pictorial representation of the hyperfine transition of neutral hydrogen."