Found 2 items, similar to rarefaction.
English → English (WordNet) Definition: rarefaction rarefaction n : a decrease in the density of something; “a sound wave causes periodic rarefactions in its medium”
English → English (gcide) Definition: Rarefaction 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]