per-

1.
a prefix meaning “through,” “thoroughly,” “utterly,” “very”:
pervert; pervade; perfect.
2.
Chemistry. a prefix used in the names of inorganic acids and their salts that possess the maximum amount of the element specified in the base word: percarbonic (H 2 C 2 O 5), permanganic (HMnO 4), persulfuric (H 2 S 2 O 8), acids; potassium permanganate (KMnO 4); potassium persulfate (K 2 S 2 O 8).
Origin
< Latin, combining form of per per, and used as an intensive
British Dictionary definitions for per-

per-

prefix
1.
through: pervade
2.
throughout: perennial
3.
away, beyond: perfidy
4.
completely, throughly: perplex
5.
(intensifier): perfervid
6.
indicating that a chemical compound contains a high proportion of a specified element: peroxide, perchloride
7.
indicating that a chemical element is in a higher than usual state of oxidation: permanganate, perchlorate
8.
(not in technical usage) a variant of peroxy- persulphuric acid
Word Origin
from Latin per through
Word Origin and History for per-

word-forming element meaning "through, throughout; thoroughly; entirely, utterly," from Latin preposition per (see per (prep.)).

per- in Medicine

per- pref.

  1. Thoroughly; completely; intensely: perfuse.

  2. Containing an element in its highest oxidation state: perchloric acid.

  3. Containing a large or the largest possible proportion of an element: peroxide.

  4. Containing the peroxy group: peracid.