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        Word: xipfne [jbovlaste]
        Type: obsolete fu'ivla
  Gloss Word: 21 cm wavelength in the sense of "color"
  Gloss Word: HI line in the sense of "color, electromagnetic emission spectrum"
  Gloss Word: hydrogenic spin-flip transition in the sense of "color"
  Gloss Word: hyperfine line in the sense of "color"
  Gloss Word: hyperfine splitting (hydrogen) color in the sense of "color, hydrogen electron"
  Gloss Word: spin-flip transition in the sense of "color"
  Gloss Word: twenty-one centimeter wavelength in the sense of "color"
  Definition: x1 emits light characteristic of/is of the color that is
       described by/(as) arising from/associated with the
       approximately twenty-one centimeter wavelength, hydrogen
       hyperfine proton/electron spin-flip transition (from parallel
       to antiparallel configuration, id est: from the higher energy
       state to the lower energy state), electromagnetic radiation
       Notes: In analogy to xunre and the like.  See also: skari,
       blabi, xekri, kandi, carmi, nukni, narju, rozgu,
       zirpu, pelxu, xunre, cidro, lektoni, protoni,
       dikca, maksi, guska'u, gusni, cradi. This color is a
       subset/element (depending on interpretation/usage) of the
       colors associated with light in the radio and microwave regions
       of the electromagnetic spectrum. Speaker determines how close
       "approximately twenty-one centimeters" is to exactly twenty-one
       centimeters. Technically can only be used for the coloration of
       light that would arise from the hyperfine spin-flip transition
       of a hydrogen atom (without any neutrons) in which the
       proton-electron quantum spin configuration abruptly changes
       from parallel to antiparallel in the 1s groundstate.  But other
       isotopes and/or hydrogenic (id est: single-electron) atoms can
       be referenced by semantic broadening; note that in any case,
       this word always refers to the color of the light emitted from
       such an object. This is a color, not a description of the
       process, conditions under which the light of this color is
       emitted, etc., nor is it the light itself nor wavelength of the
       light.  However, this term probably will come up in all such
       descriptions.  For example, "hyperfine spin-flip transition"
       might be rendered xipfne binxo. Technically, any object that
       emits photons with wavelengths of approximately twenty-one
       centimeters will be of the color xipfne, regardless of why such
       emission is occurring (id est: it need not be due to hydrogen
       hyperfine, proton/electron spin-flip transitions). Usage in
       such a case is perfectly acceptable.  However, in practice,
       such occasions/contexts will be rare (essentially completely
       absent except in theory) and the only common usage will be in
       the context of hydrogen hyperfine proton/electron spin-flip
       transitions (as in astronomy, chemistry, or quantum mechanics).
       This is an electromagnetic (id est: light, photon) color.  It
       is physical (being derived from the properties of the
       wavelength of the emitted and received photon(s)), but is
       interpreted by some instrument (such as a telescope/camera
       system, an animal's optical system, etc.). Usage need not be
       technical.
  Place Keywords:
    1. Has coloration characterized by emission of photons of approximately twenty-one centimeters in wavelength in the sense of "color"