Make Less Dense, Anagram of Friary
This page is the CodyCross answer for the clue below from Physics, Group 1899, Puzzle 3 (Interference).
Question is: Make Less Dense, Anagram of Friary
and the answer is: RARIFY
Word Meaning:
RARIFY — (sometimes proscribed) Alternative spelling of rarefy.
Definitions from Wiktionary.