per

¹

[ pur; unstressed 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 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 ).

per.

³

abbreviation for

1. percentile.
2. period.
3. person.

Per.

⁴

abbreviation for

1. Persia.
2. Persian.

per

¹

/ pə; pɜː /

determiner

1. for every

   three pence per pound

preposition

1. (esp in some Latin phrases) by; through
2. as per
   according to

   as per specifications

3. as per usual informal.
   as usual

PER

²

abbreviation for

1. Professional Employment Register

per-

³

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

   perchlorate

   permanganate

8. not in technical usage a variant of peroxy-

   persulphuric acid

Usage Note

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

C15: from Latin: by, for each

Origin of per²

from Latin per through

Example Sentences

While the vast majority of cells appeared normal, nearly all of the women harboured a small number of breast cells -- about 3 per cent -- that carried genetic alterations commonly associated with cancer.

From Science Daily

The answer, per TMZ, is they didn’t.

From Los Angeles Times

It is, he says, "one of the most expensive ways to generate electricity. Investing in cheaper low-carbon sources of energy will provide more emissions reductions per dollar."

From BBC

There were 84,300 suspensions in primary schools in 2022/23- a rate of 180 per 10,000 pupils.

From BBC

Current guidelines recommend adults perform a minimum of 150 minutes per week of moderate-intensity physical activity or 75-minutes of vigorous physical activity along with muscle strengthening for two days a week.

From Science Daily