per

¹ American  

[pur, per] / pɜr, pər /

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.

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adverb

1. Informal.  each; for each one.

   The charge for window-washing was five dollars per.

per- ² American  

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 ).

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per. ³ American  

abbreviation

1. percentile.

2. period.

3. person.

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Per. ⁴ American  

abbreviation

1. Persia.

2. Persian.

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per- ¹ British  

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

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per ² British  

/ pə, pɜː /

determiner

1. for every

   three pence per pound

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preposition

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

2. according to

   as per specifications

3. informal  as usual

PER ³ British  

abbreviation

1. Professional Employment Register

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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.

Etymology

Origin of per¹

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

Origin of per-²

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

Example Sentences

I drove over to downtown Los Angeles’ Garment District, a neighborhood that wasn’t unsafe per se, but one I’d never visit if I didn’t have to.

From Salon

Tuition at an in-state public university is, on average, $11,950 per year, according to data from the College Board.

From MarketWatch

Even in a “draconian scenario,” in which the company forfeited all incremental AI revenue beyond fiscal 2026 but was still subject to 50% of its contracted lease payments, his model arrives at $12 in earnings per share for fiscal 2030 as well as $12 billion in free cash flow.

From MarketWatch

In an upside case, Amazon could add 5 gigawatts of capacity per year over the the next two years.

From MarketWatch

Wall Street estimates imply that AWS’s revenue per gigawatt will decline and capital expenditures will remain high relative to revenue.

From MarketWatch