a
determiner
UK/ə/US/ə/
used before singular nouns to refer to any one example of a type of thing.
Example Sentences
He bought a book from the store.
I need a pen to write with.
Can you pass me a glass of water?
A dog barked loudly in the street.
It was a sunny day, so we went to the park.
Do you have a moment to talk about this?
A curious child is often full of questions.
She had a long day at work, so she went to bed early.
Thesaurus
Synonyms
Antonyms
How to Use
Short indefinite article denoting one unspecified noun.This single-letter article precedes a singular, countable noun that hasn’t been specified before. It implies “one” but not a particular one. You typically use it before consonant sounds, such as “a book” or “a cat.”
In contrast, “an” is reserved for vowel sounds, for example “an apple” or “an hour.” Whether to choose “a” or “an” depends on how the following word is pronounced, rather than just its first letter. For instance, you say “a university” because “university” starts with a “y” sound, whereas “an honor” is correct because “honor” begins with a silent “h” and thus a vowel sound.
This article helps introduce something new to your listener or reader and signals that what follows is singular and not yet identified in the context.
Alternatives
Alternatives to the Indefinite Article
Alternatives to this indefinite article depend on context. Use “an” if the next word starts with a vowel sound, such as “an idea” or “an elephant.” If you’re referring to a singular, specific item, “the” is appropriate, for instance “the book on the table.” Where quantity is uncertain or if nouns are uncountable, you might use words like “some” (e.g., “some water”). In older or very formal texts, you might see expressions like “one” used for emphasis (e.g., “one fine day”), but these carry a different nuance.
Writing
Using the Correct Article: "A" vs. "An"
When writing, ensure that you choose the correct article based on both spelling and pronunciation. “A” is used with words that begin with a consonant sound (e.g., “a car”), while “an” pairs with words that begin with a vowel sound (e.g., “an umbrella”).
Misusing these can distract readers or signal inattention to detail. Always consider whether your noun is countable, singular, and unspecified. If all these conditions are met, use this article.
Practice revising sentences to check that you have the right article before each noun.
Casual Conversation
Using "A" in Everyday Speech
In everyday speech, using “a” is straightforward: just place it in front of a singular, countable noun when you’re talking about something for the first time or talking about something non-specific. For instance: “I saw a movie yesterday,” meaning you’re introducing the movie as an unknown title.
If the noun starts with a vowel sound, remember to use “an.” Checking your pronunciation helps avoid confusion—say “a house” but “an hour.”
Over time, using the correct indefinite article becomes second nature.
Etymology
The Etymology of the Articles "A" and "An"
The article comes from an older form “an,” which in turn comes from Old English “ān,” meaning “one.” Over centuries, English pronunciation and spelling evolved, leading to distinct modern uses of “a” and “an.”
Historically, “a” and “an” were variations of the same word, but the distinction became clearer once vowel and consonant sounds took priority in determining which form to use.
It’s fascinating that a tiny article carries such a long linguistic history, tracing back to the concept of singularity.