per
1 Americanpreposition
-
for each; for every.
Membership costs ten dollars per year. This cloth is two dollars per yard.
-
by means of; by; through.
I am sending the recipe per messenger.
-
Also according to; in accordance with.
I delivered the box per your instructions.
He managed to monopolize the meeting, per usual.
adverb
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a prefix meaning “through,” “thoroughly,” “utterly,” “very”: pervert; pervade; perfect.
-
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 ).
abbreviation
-
percentile.
-
period.
-
person.
abbreviation
-
Persia.
-
Persian.
prefix
-
through
pervade
-
throughout
perennial
-
away, beyond
perfidy
-
completely, throughly
perplex
-
(intensifier)
perfervid
-
indicating that a chemical compound contains a high proportion of a specified element
peroxide
perchloride
-
indicating that a chemical element is in a higher than usual state of oxidation
permanganate
perchlorate
-
(not in technical usage) a variant of peroxy-
persulphuric acid
determiner
preposition
-
(esp in some Latin phrases) by; through
-
according to
as per specifications
-
informal as usual
abbreviation
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”; see for
Origin of per-2
From Latin, combining form of per, and used as an intensive; per
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The Academy of Nutrition and Dietetics has issued a dietary recommendation suggesting 400 to 600 milligrams of flavanols per day for cardiometabolic health.
From Science Daily • May 24, 2026
She’s averaged seven fouls per 36 minutes in her first two seasons.
From Los Angeles Times • May 23, 2026
They regulate attendance through an opaque system of visa quotas that roughly grants one spot per 1,000 Muslims in each country, though that can sometimes be negotiated.
From The Wall Street Journal • May 23, 2026
O'Neill achieved it with a win rate of well over 80 per cent.
From BBC • May 23, 2026
Brooklyn stared out the window at a landscape of green, yellow, and brown as the Eurostar raced through the French countryside, going nearly 190 miles per hour.
From "City Spies" by James Ponti
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.