per

¹

[pur, per]

preposition

1. for each; for every.

   Membership costs ten dollars per year. This cloth is two dollars per yard.

2. by means of; by; through.

   I am sending the recipe per messenger.

3. Also according to; in accordance with.

   I delivered the box per your instructions.

   He managed to monopolize the meeting, per usual.

adverb

1. Informal.,  each; for each one.

   The charge for window-washing was five dollars per.

per-

²

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 O5 ), permanganic (HMnO4 ), persulfuric (H 2 S 2 O8 ), acids; potassium permanganate (KMnO4 ); potassium persulfate (K 2 S 2 O8 ).

per.

³

abbreviation

1. percentile.

2. period.

3. person.

Per.

⁴

abbreviation

1. Persia.

2. Persian.

per-

¹

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

per

²

/ pə, pɜː /

determiner

1. for every

   three pence per pound

preposition

1. (esp in some Latin phrases) by; through

2. according to

   as per specifications

3. informal,  as usual

PER

³

abbreviation

1. Professional Employment Register

Usage

Per meaning a or an or for each occurs chiefly in technical or statistical contexts: miles per gallon; work-hours per week; feet per second; gallons of beer per person per year. It is also common in sports commentary: He averaged 16 points per quarter. Per is sometimes criticized in business writing in the sense “according to” and is rare in literary writing.

Word History and Origins

Origin of per¹

First recorded in 1580–90; from Latin: “through, by, for, for each”; for

Origin of per²

From Latin, combining form of per, and used as an intensive; per

Word History and Origins

Origin of per¹

from Latin per through

Origin of per²

C15: from Latin: by, for each

Example Sentences

Since 2010, their water intake has been reduced by 29% to about 0.55 barrel of water per barrel of crude, Flint Hills said last year.

Read more on The Wall Street Journal

He told the programme NHS waiting lists were coming down, GP numbers were going up and more affordable houses were being built in Scotland per head of the population.

Read more on BBC

It was similarly stifling against the run, holding Michigan’s top rushing attack to a meager 3.5 yards per carry.

Read more on Los Angeles Times

For commercial organisations using Windows 10, it will cost $61 per device.

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Tuesday, rain will fall at a rate of about 0.10 to 0.33 of an inch per hour, the weather service predicted.

Read more on Los Angeles Times