(pûr) prep.
1. By; by means of; through: used in commercial and business English: per bearer.
2. To or for each: ten cents per yard.
3. By the; every: especially in Latin phrases: per diem. [<L, through, by]

1. Through; throughout: pervade, perennial.
2. Thoroughly; completely: perturb.
3. Away: pervert, peremptory.
4. Very: perfervid.
5. Chem. a Denoting the higher degree of valence in two similar compounds: barium peroxide as distinguished from barium monoxide. b Indicating a relatively large amount of the compound or radical named: perchloric acid, contrasted with chloric acid. ♦ The prefix occurs in other forms in pardon, paramour, pellucid, etc. [<L per through, by means of; in some words <OF or F]