1 forming verbs, nouns, and adjectives meaning: a through; all over (perforate; perforation; pervade). b completely; very (perfervid; perturb). c to destruction; to the bad (pervert; perdition).
2 Chem. having the maximum of some element in combination, esp.: a in the names of binary compounds in -ide (peroxide). b in the names of oxides, acids, etc. in -ic (perchloric; permanganic). c in the names of salts of these acids (perchlorate; permanganate).
L per- (as PER)