1) Alter 2) Become less dense 3) Become thinned 4) Change 5) French word used in English 6) Lessen the density of 7) Make less dense 8) Make more refined 9) Make more subtle 10) Make more subtle or refined 11) Make purer 12) Make thin or less dense 13) Make thin or porous 14) Make thinner 15) Modify 1) Fade 
The Librarian: Curse of the Judas Chalice is the third and final film in The Librarian trilogy of movies starring Noah Wyle as a librarian who protects a secret collection of artifacts from Vlad Dracula and his vampire hordes. It is a sequel to 2004`s The Librarian: Quest for the Spear and 2006`s The Librarian: Return to King Solomon`s Mines. =......
• (v. i.) To become less dense; to become thin and porous. • (v. t.) To make rare, thin, porous, or less dense; to expand or enlarge without adding any new portion of matter to; -- opposed to condense.
To become light or less dense. ... (05 Mar 2000) ... 
Rar'e·fy (răr'e*fī; 277) transitive verb [ imperfect & past participle Rarefied (- fīd); present participle & verbal noun Rarefying (- fī`ĭng).] [ French raréfier ; Latin rarus rare + ...Rar'e·fy intransitive verb To become less dense; to become thin and porous. 'Earth rarefies to dew.' Dryden. 
to make thin to make less dense to purify or refine 
Type: Term Pronunciation: rār′ĕ-fī Definitions: 1. To become light or less dense.
[v] - lessen the density or solidity (of a substance) 2. [v] - make more subtle or refined 3. [v] - weaken the consistency of (a chemical substance)
verb make more subtle or refined