An Hilarious or A Hilarious? Which Is Correct?

I once heard someone say, “That was an hilarious joke,” and it instantly triggered my grammar radar. It felt off. And that’s because it is. When discussing whether to use “a” or “an,” the rule isn’t based on how the word is spelled – it’s all about how it sounds. In “An Hilarious or A Hilarious” the focus is on the pronunciation. Since hilarious begins with a hard “h” sound, the correct article is clearly “a hilarious,” not “an hilarious.” That small difference changes how the sentence feels – more natural, more right.

Compare with “a hotel,” “a hat,” or “a hero.” They all begin with the same kind of pronunciation as “hilarious.” That’s why it makes sense to say “a hilarious.” Once you’ve seen this pattern, it really settles the confusion. It’s not just about grammar rules – it’s about understanding how the language flows and what shows a strong instinct for grammar.

Understanding Indefinite Articles: “A” vs “An”

Before we dive into the hilarious confusion, let’s talk about what indefinite articles are.

In English, the two indefinite articles are:

• “A” – used before words that start with a consonant sound
• “An” – used before words that start with a vowel sound

You use them when you’re referring to a non-specific thing. For example:

• I saw a cat on the roof.
• She gave me an envelope.

The article doesn’t define which cat or which envelope – just that there’s one.

But here’s the kicker: it’s not about letters – it’s all about sounds.

The Sound Rule: Not Spelling, But Pronunciation

Most people mistakenly think “a” and “an” depend on spelling. But English grammar doesn’t work that way.

✅ The rule: Use “an” before a word that begins with a vowel sound. Use “a” before a word that begins with a consonant sound.

That means:

• It’s an honest mistake → because “honest” starts with a silent H (vowel sound: /ɑ/).
• It’s a hilarious story → because “hilarious” starts with an H sound (consonant: /h/).

Let’s explore further.

Is It “A Hilarious” or “An Hilarious”? The Correct Form

Here’s the correct answer:

✅ It’s always “a hilarious”, never “an hilarious” in modern English.

Why?

“Hilarious” starts with a voiced H sound: /hɪˈlɛəriəs/. That’s a consonant sound, not a vowel sound.

Even though “h” is sometimes silent in other words (hour, honest), it is clearly pronounced in “hilarious.”

You wouldn’t say an hat or an house, would you? Same logic applies here.

Phonetics Breakdown: The Pronunciation of “Hilarious”

To really understand this, let’s look at the phonetic transcription:

• Word: hilarious
• Pronunciation (IPA): /hɪˈlɛəriəs/

Notice the strong “h” at the beginning. That makes all the difference.

Why Some Say “An Hilarious” – The Misguided Exception

You might hear “an hilarious” in older books, speeches, or from people trying to sound formal or British. But that doesn’t make it correct today.

Historical Context:

• In older British English, the “h” in words like historical and hilarious was often softened or dropped.
• That led some writers to use “an” instead of “a.”

However, in modern pronunciation, the “h” in hilarious is strong and voiced. Grammar rules have caught up.

Even major style guides like The Chicago Manual of Style, APA, and Merriam-Webster recommend using “a hilarious”.

Common H-Words and Their Correct Articles

Let’s look at a table of confusing “H” words and which article fits:

Word	Correct Article	Reason
Hilarious	a hilarious	Pronounced H sound
Hour	an hour	Silent H → starts with vowel
Honest	an honest	Silent H → starts with vowel
Historical	a historical	H is pronounced in modern usage
Herb (US)	an herb	H is silent in American English
Herb (UK)	a herb	H is pronounced in British English

This breakdown shows how pronunciation – not spelling – determines the article.

When “An” Is the Right Choice: The Silent H Rule

There are exceptions. These happen when the H is completely silent, making the word start with a vowel sound.

Correct “An” Examples:

• An hour
• An honest answer
• An honor to meet you

Here, “an” is absolutely correct because the H disappears when spoken.

Real Examples: “A Hilarious” in Use

Let’s test this in real, everyday sentences.

✅ Correct:

• That was a hilarious movie – I couldn’t stop laughing.
• She cracked a hilarious joke at the party.
• He made a hilarious observation during the meeting.

❌ Incorrect:

• It was an hilarious moment. (Sounds awkward, outdated)

Modern readers and grammar tools will flag this instantly.

Case Study: Google Books Corpus and Real Usage

Let’s compare actual usage data from the Google Books Ngram Viewer:

• “A hilarious” appears significantly more than “an hilarious” since the 1950s.
• Usage of “an hilarious” peaked in early 20th-century British texts and then declined rapidly.

Takeaway: Modern English – across books, news, and speech – overwhelmingly favors “a hilarious.”

The Role of Style Guides and Expert Opinions

Let’s take a look at what trusted sources say:

“Use ‘an’ only before words that begin with a vowel sound, not just a vowel letter.”  –  Merriam-Webster Dictionary

“In modern usage, ‘a historical’ and ‘a hilarious’ are preferred, as the ‘h’ is clearly pronounced.”  –  The Chicago Manual of Style

These aren’t just grammar opinions – they’re standards followed by writers, editors, and linguists.

What About Speech? Listening Is Key

When in doubt, say it aloud. If your mouth naturally pauses or stumbles on “an hilarious,” that’s your clue. Your ear knows.

Try this out loud:

• “It was a hilarious idea.”
• “It was an hilarious idea.”

Which sounds more natural?

Even in casual speech, “a hilarious” flows more smoothly because of that firm “h” sound at the beginning.

American vs. British English: Does It Matter?

Sometimes. But not here.

Key differences:

• In British English, “herb” is pronounced with an H → a herb
• In American English, “herb” is pronounced without an H → an herb

But for “hilarious”? Both American and British speakers pronounce the H, making “a hilarious” correct in both dialects.

Checklist: How to Choose Between “A” and “An” Instantly

Use this quick, foolproof method:

✅ The 3-Second Rule:

1. Say the next word aloud.
2. If it starts with a vowel sound, use an.
3. If it starts with a consonant sound, use a.

Don’t trust the letter. Trust the sound.

Grammar Mistakes to Avoid With H-Words

Here’s where people trip up:

• ❌ Using “an” for all H-words
• ❌ Copying outdated British formal writing
• ❌ Over-correcting because “it looks wrong”
• ❌ Ignoring pronunciation

Stick to the rule of sound, and you’re golden.

Final Thoughts:

When it comes to choosing between “an hilarious” or “a hilarious,” there’s no room for debate in modern English. The correct form is – and has been – “a hilarious.” Why? Because “hilarious” starts with a pronounced H sound, which means it takes the article “a,” not “an.”

The confusion often comes from outdated British usage or the mistaken belief that the choice of article depends on the first letter rather than the first sound. But grammar – and real-world usage – makes it clear: sound always wins.

Even though you may stumble upon “an hilarious” in older books, speeches, or attempts at sounding refined, today’s grammar standards and dictionaries strongly discourage it. Using “a hilarious” reflects both correct grammar and natural, modern speech.

FAQs:

Is it grammatically correct to say “an hilarious”?

No, it’s not correct in modern English. “Hilarious” starts with a pronounced H sound, making “a hilarious” the proper choice according to current grammar standards.

Why do people still use “an hilarious”?

It lingers from older British English where the “h” was sometimes softly spoken or dropped. Today, however, the H in “hilarious” is pronounced, so “an hilarious” sounds awkward and outdated.

Does the choice depend on spelling or sound?

Sound. Always. “A” goes before words that begin with a consonant sound, while “an” goes before vowel sounds. Spelling doesn’t always reflect pronunciation – like in “an hour.”

Is it different in British vs. American English?

Not for “hilarious.” Both British and American English pronounce the H, so both use “a hilarious.” However, the word “herb” differs: Americans say “an herb,” while Brits say “a herb.”

What are other examples of this rule?

Use “an” before: an hour, an honest man. Use “a” before: a house, a hotel, a hilarious movie. Just say the word aloud. If it starts with a vowel sound, use “an.” Otherwise, use “a.”