When we talk about language, even confident speakers may find themselves tripping over tricky rules that create confusion. One common debate that never seems to end is whether to say “A Hilarious or An Hilarious.” At first glance, both can sound correct, and I’ve heard people use them in conversation.
However, one clearly aligns with modern grammar and pronunciation, while the other belongs to history and older usage.As someone who enjoys studying words and how they shape thought, I’ve gone through countless articles on indefinite forms and how sound, not spelling, truly decides the right form.
We learn that words beginning with a vowel sound take “an,” and those starting with a consonant sound use “a.” Since the h in hilarious is strongly pronounced, the phrase “a hilarious moment” is grammatically right, unlike “an hilarious story.” These tiny details often confuse writers, especially those who uncover or imitateclassical tones in their writing
What Are Indefinite Articles in English?
English relies on articles to show whether we’re talking about something specific or general. There are two main types:
- Definite article: the (used for something specific, e.g., the cat on the roof).
- Indefinite articles: a and an (used for general or nonspecific nouns, e.g., a book on the table).
Indefinite articles act like little signposts. They prepare the reader or listener for a noun without committing to which exact one. For example:
- She bought a car. (any car, not a specific one)
- I’d love an apple. (any apple will do)
They may look small, but they play a critical role in clarity and flow.
The Core Rule: A vs. An
The guiding principle is simple, but surprisingly easy to misuse.
- Use a before words that start with a consonant sound.
- Use an before words that start with a vowel sound.
Notice the key word: sound. This isn’t about spelling. It’s about how the word actually begins when spoken.
Examples:
- a dog (consonant sound /d/)
- a university (begins with /juː/, a consonant y sound)
- an apple (vowel sound /æ/)
- an hour (silent h, begins with vowel sound /aʊ/)
Rule of thumb: always say the word aloud. The ear never lies.
The H-Words Dilemma
Now, here’s where things get messy. Words beginning with h often cause confusion. Why? Because the English letter h can behave two very different ways.
- Aspirated h – pronounced strongly, as in hilarious, happy, hotel.
- Silent h – completely dropped, as in honor, honest, heir.
The problem: older forms of English often dropped the h sound in words where today we pronounce it. This historical variation explains why you sometimes see an historical or an hilarious in older writing.
In modern speech though, most h words—including hilarious—are aspirated and require a.
A Hilarious: The Correct Form
So, let’s settle it clearly:
- Correct: a hilarious joke
- Incorrect: an hilarious joke
Why? Because the word hilarious begins with the consonant sound /h/. Modern English rules require a before consonant sounds.
To prove this, let’s look at real-world usage:
- The comedian told a hilarious story about his family vacation. (The New York Times)
- It was a hilarious scene that had the crowd roaring with laughter. (BBC News)
You’ll struggle to find reputable modern sources using an hilarious—and when you do, it’s usually for stylistic effect or as an echo of older usage.
An Hilarious: Where the Misconception Comes From
If a hilarious is correct, why do people still say or write an hilarious?
The answer lies in history and hypercorrection.
- In 18th and 19th century British English, dropping the h sound was common in words like historic, hospital, and hilarious. Writers used an to match the vowel sound.
- Over time, as pronunciation shifted and h became more aspirated, a became the standard article.
Some people cling to an hilarious because they believe it sounds more formal or “old-fashioned.”
But make no mistake: in today’s English, it’s outdated. Modern style guides—including the Chicago Manual of Style and Oxford English Dictionary—favor a hilarious
Pronunciation Determines Article Choice
The best way to understand this is to focus on sound, not letters. Here’s a table showing how article choice depends on pronunciation:
Word | Starts With | Sound Type | Correct Article |
hilarious | /h/ (consonant) | Aspirated | a hilarious |
honor | silent /h/ → /ɑː/ (vowel) | Silent h | an honor |
hotel | /h/ (consonant) | Aspirated | a hotel |
heir | silent /h/ → /ɛ/ (vowel) | Silent h | an heir |
hour | silent /h/ → /aʊ/ (vowel) | Silent h | an hour |
Think of articles as sound-driven tools. If your ear hears a vowel sound first, go with an. If it hears a consonant sound, go with a.
Common Errors with A/An Before H-Words
Writers often trip up when dealing with h words. The three most common mistakes include:
- Using an before aspirated h words.
- Wrong: an hilarious movie
- Correct: a hilarious movie
- Overcorrecting because of formality.
- Some assume an sounds “smarter” in front of certain words. In reality, it makes writing sound dated.
- Ignoring regional pronunciation.
- In some dialects, historic or hotel may be pronounced without h. In those cases, locals might say an historic event—but global usage has shifted to a historic event.
The Silent H Exception
Of course, exceptions exist. A small set of English words begin with a silent h. These words take an, not a.
Examples of silent h words:
- an honor
- an honest mistake
- an heir to the throne
- an hour of sleep
Memorize this short list and you’ll avoid 99% of mistakes.
Case Study: A Historical vs. An Historical
The debate around a historical versus an historical mirrors the hilarious question.
- Older British usage: an historical novel (reflecting dropped h sound).
- Modern preference: a historical novel (reflecting aspirated h).
Even the Oxford English Dictionary notes that an historical is old-fashioned, while a historical is the current standard.
This pattern applies to hilarious as well. The form an hilarious is a relic, not the rule.
Why This Matters: Clarity and Confidence in Writing
Does it really matter if you write an hilarious instead of a hilarious? Absolutely.
- Clarity: The correct article prevents readers from stumbling.
- Authority: Proper grammar signals competence, especially in academic or professional settings.
- Consistency: Following modern standards aligns your writing with respected style guides.
Think of it like showing up to a meeting in the right attire. No one might say anything if you don’t—but people notice.
Practical Tips for Choosing A or An
Here’s a quick method to lock this in:
- Say the word aloud. Trust your ears.
- Check the starting sound. Consonant sound → a, vowel sound → an.
- Remember silent h words. They’re the exception, not the rule.
- Ignore outdated advice. Modern English doesn’t require an before aspirated h.
Conclusion
Understanding the correct choice between a hilarious and an hilarious is more than just a grammar rule—it’s about how language naturally evolves with time and pronunciation. While an hilarious once appeared frequently in older English due to the softer “h” sound, today’s modern speakers pronounce the “h” clearly. That makes a hilarious the proper and natural choice in everyday usage. The distinction reflects how speech patterns influence written expression, and how what was once correct may now sound awkward. Grammar rules may seem rigid, but they adapt as the way we speak changes.
In my own learning and teaching experience, I’ve realized that grammar should guide clarity, not restrict it. The phrase a hilarious aligns with the rhythm of modern grammar and makes communication smoother. English thrives on logic built around sound—whether a word starts with a vowel or a consonant sound determines our choice of article. Understanding this not only clears confusion but also builds confidence in writing and speech. So, when you next encounter the debate, remember that language breathes and shifts with usage. Follow pronunciation, not tradition, and you’ll always choose the right form with ease.
FAQs
Why do people get confused between “a hilarious” and “an hilarious”?
The confusion arises because older English once dropped the “h” sound, making “an hilarious” correct. In modern pronunciation, the “h” is clearly spoken, so “a hilarious” is now grammatically correct.
Which one is grammatically correct today?
In today’s English, “a hilarious” is the correct form. The article “a” fits words that start with a consonant sound, like the pronounced “h” in “hilarious.”
Was “an hilarious” ever considered correct?
Yes. During earlier centuries, especially in British English, the “h” in words like “hilarious” was often silent, making “an hilarious” acceptable.
Why did the rule change over time?
Language evolves with pronunciation. As the “h” sound in “hilarious” became commonly pronounced, the article “a” replaced “an” to match modern speech.
How can I decide between “a” and “an”?
Use “a” before words beginning with consonant sounds and “an” before vowel sounds. The rule depends on sound, not spelling.

Emma Brooke is a passionate English educator, writer, and language enthusiast with over a decade of experience helping learners master the nuances of the English language. At SynoEnglish, she blends practical grammar advice with real-world communication tips to make English easier, clearer, and more enjoyable for readers of all levels.