Grammar & Word Confusion: A and An

Posted March 14, 2012 by Kathy Davie in Author Resources, Grammar Explanations, Self-Editing, Word Confusions, Writing

Revised as of
12 Sept 2023

Indefinite: In grammar, an indefinite article does not point to a specific person, thing, time, or anything else.

Contrary to what we learned as kids, “a” is not automatically used before words beginning with a consonant while “an” does not automatically precede words beginning with a vowel.

The critical determination as to which indefinite article to use is the initial sound of the word and not the initial letter (a).

Keep in mind that the self-editing pages will probably never be complete. There’s always a new term someone, somewhere, uses to describe a part of grammar. Or there’s a better way to explain it, so it makes quicker and/or better sense, so I would appreciate suggestions and comments from anyone . . .

Grammar Explanations and Word Confusions sometimes . . .

. . . involve the same words as it does in here in this post on “A and An”. Whereas a Word Confusion is a pair (or more) of words that are confused spelling-wise with each other, a Grammar Explanation may jump in because of the confusion involved in how the words are used within the structural rules and principles of English.

Sometimes I run across an example that helps explain better or another “also known as”. Heck, there’s always a better way to explain it, so if you have an idea or suggestion that makes quicker and/or better sense, I would appreciate suggestions and comments from anyone . . . as well as questions on issues with which you are frustrated. If you’d like to track it, bookmark this page.

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A An

A camel standing in profile

Camelus dromedarius in Singapore Zoo is Daderot’s own work and is in the public domain, via Wikimedia Commons.

A camel at the Singapore Zoo.


An ostrich standing in profile in a wide plain

An Ostrich in the Crater by Chad Rosenthal from Jerusalem, Israel, is under the CC BY 2.0 license, via Wikimedia Commons.

Part of Grammar:
Abbreviation 1, 2, 9;
Indefinite article (a.k.a. determiner) 4;
Noun 10;
Prefix 1, 3, 5, 6;
Suffix 1, 7, 8
Indefinite article (a.k.a. determiner) 1;
Prefix 2, 3;
Proper noun 4;
Suffix 5
Grammar Usage: Use a before words that begin with a consonant sound.

Acronyms require a bit more attention, as the acronym may begin with a consonant but be pronounced as if it were a vowel or the acronym may be pronounced like a word or by its initials. Pay particular attention to the hs.

Grammar Usage: Use an before words that begin with a vowel sound.

Most acronyms and words beginning with an h and pronounced with an aitch sound will use an in front of it.

Grammar Examples:
a HAZ-MAT
a Hz
a HomePNA
a HEPNET

This is a NATO operation.

That’s a NAK

a 404 message
a 303 area code

an HCL
an HDTV
an HTTP

That’s an NFS.

Ya got an NiCD?

That’s an NIS system.

an 800 number
an 11 on a ten scale

an @ sign

Rule: When “eu” sounds like “yer” or “y” Rule: When “F” sounds like “eff”
a Europe
a European
a eulogy
an f
Rule: When “ou” sounds like “wah”, “wan”, or “wee” (Sample) Rule: When “h” sounds like “oh” or “ow” or has a silent “h”
a Quija board
a ouananiche (pronounced wan-an-ish)
a one-man
an hotel
an hour and a half
an honor
an honest
an heir
an honorable
Rule: When “u” sounds like “yoo” Rule: When “L” sounds like “el”
a unicorn
a uniform
a unique
a union
a use
a united
a U-boat
an L-plate
an LED
Rule: When “m” sounds like “em”
an M&M
an MD
Rule: When “n” sounds like “en”
an Ndebele
an NIS
Rule: When “s” sounds like “es”
an S/N
an s-shape
Rule: When “x” sounds like “ex”
an x-ray
Grammar Definitions:
Abbreviation:
[In travel timetables] Arrives 1

[In combination; in units of measurement] atto-, denotes a factor of 10−18

[British; with reference to sporting fixtures] Away

[Used before a date] Before 2

[Physics; symbol] Acceleration

[Used in describing play in bridge and other card games] Ace

Ångstrom(s)

Answer

[In personal ads] Asian

A dry cell battery size

[British; informal] A level

Ampere(s) 9

Indefinite Article:
The form used before words beginning with a consonant sound.


Used when referring to someone or something for the first time in a text or conversation 4

  • Used with units of measurement to mean one such unit
  • [With negative] One single, any
  • Used when mentioning the name of someone not known to the speaker
  • Someone like (the name specified)

Used to indicate membership of a class of people or things

Used when expressing rates or ratios

  • In
  • To
  • For each
  • Per

Noun:
The first letter of the alphabet 10

  • Denoting the first in a set of items, categories, sizes, etc.
  • Denoting the first of two or more hypothetical people or things
  • The highest class of academic mark
  • [Chess] Denoting the first file from the left, as viewed from white’s side of the board
  • The first fixed quantity in an algebraic expression
  • The human blood type (in the ABO system)
  • A shape like that of a capital A
  • [Music] The sixth note of the diatonic scale of C major
    • A key based on a scale with A as its keynote

Prefix:
To 1

Toward

  • In a specified state or manner
  • In the process of an activity
  • On
  • In

Variant spelling of ad- assimilated before sc, sp, and st

Not 3

Without

Of 5

Utterly 6

Suffix:
Forming plural nouns 1


From Greek or Latin neuter plurals corresponding to a singular in -um or -on

In names (often from modern Latin) of zoological groups


Forming 7:

  • Ancient or Latinized modern names of animals and plants
  • Names of oxides
  • Geographical names
  • Ancient or Latinized modern feminine forenames
  • Nouns from Italian, Portuguese, and Spanish

[Informal] Have 8

To

Indefinite Article:
The form used before words beginning with a vowel sound.


Used when referring to someone or something for the first time in a text or conversation 1

  • Someone like (the name specified)
  • Used to indicate membership of a class of people or things

Prefix:
Variant spelling of a- before a vowel 2

Variant spelling of ad- assimilated before n 3

Variant spelling of ana- shortened before a vowel

Proper noun:
A Sumerian god of the sky 4

Suffix:
The form used in creating adjectives and nouns, especially from 5:

  • Names of places
  • Names of systems
  • Names of zoological classes or orders
  • Names of founders or leaders when referring to them as sources
  • [Chemistry] Forming names of organic compounds, chiefly polysaccharides
Sentence Examples:
Abbreviation:
Penzance a 0915.

Derived from the Danish word atten, α means eighteen.

March 15 Sheffield United (a).

a1200

That hottie is a Leo.

I’m an A looking for a partner interested in walks on the beach and a glass of wine.

“An electric current of one ampere, flowing for one hour, removes 1.2533 grammes of zinc from a solution of sulphate of zinc” (Ampere).

An Å is used to measure the wavelength of electromagnetic radiation or distances between atoms.

Indefinite Article:
A man came out of the room.

It has been a joy to have you.

We need people with a knowledge of languages.

Gimme a hundred.

I simply haven’t a thing to wear.

A Mr. Smith telephoned.

You’re no better than a Hitler.

He is a lawyer.

This car is a BMW.

She was typing 60 words a minute.

We need people with a knowledge of languages.

It cost as much as eight dollars a dozen.

An ant came out of its hole.

It has been an honor to have you.

It should only take a quarter of an hour.

You’re no better than an idiot.

He is an editor.

This car is an Audi.

Acronyms:
This is a NATO operation.

That’s a NAK.

That’s an NFS.

Ya got an NiCD?

That’s an NIS system.

Other acronyms and words beginning with “h” and sounding like it will use “a”:

  • a HAZ-MAT
  • a Hz
  • a HomePNA
  • a HEPNET
Most acronyms and words beginning with an “h” starting with an “aitch” sound and will use “an” in front of it:

  • an HCL
  • an HDTV
  • an HTTP

The same is true for other vowel-starting acronyms and words when:

  • “Eu” sounds like “yer” or “y”
    • a Europe
    • a European
    • a eulogy
  • “Ou” sounds like “wah”, “wan”, or “wee” (Sample)
    • a Quija board
    • a ouananiche (pronounced wan-an-ish)
    • a one-man
  • “U” sounds like “yoo”
    • a unicorn
    • a uniform
    • a unique
    • a union
    • a use
    • a united
    • a U-boat
The same is true for other consonant-starting acronyms and words when:

  • “F” sounds like “eff”
    • an f
  • “H” sounds like “oh” or “ow” or has a silent “h”
    • an hotel
    • an hour and a half
    • an honor
    • an honest
    • an heir
    • an honorable
  • “L” sounds like “el”
    • an L-plate
    • an LED
  • “M” sounds like “em”
    • an M&M
    • an MD
  • “N” sounds like “en”
    • an Ndebele
    • an NIS
  • “S” sounds like “es”
    • an S/N
    • an s-shape
  • “X” sounds like “ex”
    • an x-ray
Noun Proper noun
(Using a as a noun will vary in whether you use a or an preceding it)


A is for apple.

Let’s suppose that a B had killed F.

The Gringmuth notation for White’s side of a chess board is an A.

32 = 2a + 8

His blood type is A.

Mom! Mom! I got an A.

What about an A-frame?

The key signature for the A major scale includes three sharps.

(Using an as a noun — and this was a stretch!)


An is a Sumerian sky god.
Prefix
He pulled him aside for a quiet chat.

All ashore who’s going ashore.

Dude, I was asleep.

Mother read the story aloud to us all.

Daddy’s gone a-hunting.

The game’s a-foot.

Nowadays you young whippersnappers just up and go.

She ascended those stairs like an angel.

I aspire to greater things in my career.

Whoa, that lemonade is quite astringent.

I’m not an atheist but an agnostic.

It’s an atypical result.

She raised those questions anew.

He was abashed when she turned him down.

If you have anemia, you should eat foods rich in iron.

We need an anechoic chamber to record this.

The Battle of Austerlitz was an annihilation.

Any documentation should be annotated with explanatory notes.

He had an aneurysm. No one saw it coming.

Suffix
There are addenda at the end of the book.

They are truly a phenomena.

“Insectivora have long been recognized as being amongst the most primitive of placental mammals” (Basal).

I thought I’d plant primulas in that bend of the garden.

“When warmed with baryta water it gives uvitic acid” (Baryta).

We lived in Africa for two years.

“Oh, Lydia, oh, Lydia. Oh, have you seen Lydia. Lydia the tattooed lady.”

She must have a duenna with her at all times.

A stanza is a group of lines in a poem.

You know what those Ohioans are like.

I love that movie The Russians are Coming, The Russians are Coming.

No, Henry isn’t an Anglican or a Presbyterian.

Mary loves to eat crustaceans.

Chomskyan linguistics challenges structural linguistics and introduces transformational grammar.

Dextran is used medicinally as an antithrombotic to reduce blood viscosity and as a volume expander in hypovolaemia.

History of the Word:
  1. Old English as an unstressed form of on.
  2. From the Latin ante.
  3. From the Greek.
  4. Middle English in a weak form of Old English ān meaning one.
  5. Unstressed form of of.
  6. Anglo-Norman French and corresponding to the Old French e- or es-, from the Latin ex.
  7. Represents a Greek, Latin, or Romance feminine singular.
  8. Represents a casual pronunciation.
  9. Late 19th century, named after A. M. Ampère.
  10. Unknown.
  1. Middle English as a weak form of Old English ān meaning one.
  2. From the Greek.
  3. From the Greek ana meaning up.
  4. Unknown.
  5. Based on the Latin -(i)anus and -aeus adjectival endings.

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C’mon, get it out of your system, bitch, whine, moan . . . which words are your pet peeves? Also, please note that I try to be as accurate as I can, but mistakes happen or I miss something. Email me if you find errors, so I can fix them . . . and we’ll all benefit!

Satisfy your curiosity about other Grammar Explanations by exploring its homepage or more generally explore the index of self-editing posts. You may also want to explore Book Layout & Formatting Ideas, Formatting Tips, Grammar Explanations, Linguistics, Publishing Tips, the Properly Punctuated, Word Confusions, Writing Ideas and Resources, and Working Your Website.

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Resources for A and An

Some of these links may be affiliate links, and I will earn a small percentage, if you should buy it. It does not affect the price you pay.

“a, an: Grammatical Articles.” English Word Information. n.d. Accessed n.d. <http://wordinfo.info/unit/3431/ip:1>.

Apple Dictionary

“Basal Insectivores & Golden Moles.” Insectivora. Palaeos. n.d. Accessed n.d. <http://palaeos.com/vertebrates/insectivora/insectivora.html>.

“How to Use Ampere in a Sentence.” Sentence. Your Dictionary.com. n.d. Accessed n.d. <https://sentence.yourdictionary.com/ampere>.

“How to Use Baryta in a Sentence.” Sentence. YourDictionary.com. n.d. Accessed n.d.

“Sample Lessons.” North American Montessori Center. n.d. Accessed n.d. <http://www.montessoritraining.net/element_program2/courses/language_arts1/sample_lessons.pdf>.

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Pinterest Photo Credits

Green Chalkboard, <https://visualhunt.com/photo/103885/>, is in the public domain, via VisualHunt while the frame is from Blackboard, which is in the public domain, via Pixnio.

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