Search Result for "rarefying": 

The Collaborative International Dictionary of English v.0.48:

Rarefy \Rar"e*fy\ (r[a^]r"[-e]*f[imac]; 277), v. t. [imp. & p. p. Rarefied (r[a^]r"[-e]*f[imac]d); p. pr. & vb. n. Rarefying (r[a^]r"[-e]*f[imac]`[i^]ng).] [F. rar['e]fier; L. rarus rare + -ficare (in comp.) to make; cf. L. rarefacere. See -fy.] To make rare, thin, porous, or less dense; to expand or enlarge without adding any new portion of matter to; -- opposed to condense. [1913 Webster]