rarefacio

Latin > English (Lewis & Short)

rārē-făcĭo: (written also separately rārē făcĭo), fēci, factum, 3, v. a. rarus,
I to make thin or rare, to rarefy (Lucret.): rarefieri, Lucr. 1, 648: rarefacta, id. 2, 1139; 3, 442: rareque facit, id. 6, 233; 870.

Latin > French (Gaffiot 2016)

rārēfăcĭō,¹⁴ fēcī, factum, ĕre (rarus, facio), tr., raréfier : Lucr. 6, 233