rarefaction

2 definitions found

rarefaction - Collaborative International Dictionary of English v.0.48 :

  Rarefaction \Rar`e*fac"tion\ (r[a^]r`[-e]*f[a^]k"sh[u^]n), n.
     [Cf. F. rar['e]faction. See Rarefy.]
     The act or process of rarefying; the state of being rarefied;
     -- opposed to condensation; as, the rarefaction of air.
     [1913 Webster]

rarefaction - WordNet (r) 2.1 (2005) :

  rarefaction
      n 1: a decrease in the density of something; "a sound wave
           causes periodic rarefactions in its medium"