How to use "a unreasonable"

What Does "a unreasonable" Mean?

• The phrase "a unreasonable" is grammatically incorrect. The correct phrase is "an unreasonable." "Unreasonable" means not guided by or based on good sense.
• The meaning is compositional, as it's simply the combination of the indefinite article and the adjective "unreasonable."
• Register: Neutral

How to Use It

• Grammatical pattern: Article + Adjective + Noun (e.g., an unreasonable request, an unreasonable amount).
• Typical nouns that follow: request, demand, expectation, fear, amount, time, response, assumption, offer, inference, concern.
• The components cannot be separated (e.g., "a very unreasonable" is correct, but inserting words between "a" and "unreasonable" is not).
• What sounds unnatural: Using "a" instead of "an" before "unreasonable"; using "unreasonable" as a verb or noun.

Real-World Examples

These examples are sourced from a unreasonable on Ludwig.guru.

"The royal couple took action because of a "unreasonable" pattern of behaviour allegedly displayed by the individual, a freelancer, described as tantamount to following the 14-month-old prince and his nanny around." — The Guardian

"What's an example of an unreasonable fear?" — Huffington Post

"And seriously, it was an unreasonable amount." — HuffPost

"Or is that an unreasonable expectation for a boss?" — The New York Times

"A deep-seated cynicism is not an unreasonable response." — Huffington Post

Examples sourced from https://ludwig.guru/s/a+unreasonable

Similar Phrases and Alternatives

Phrase	Context
an excessive	Implies exceeding a normal or acceptable limit.
an unwarranted	Suggests lacking justification or reason.
an unjustifiable	Similar to unwarranted, emphasizing a lack of defensible reason.
an exorbitant	Used primarily to describe prices or costs that are unreasonably high.
an outrageous	Suggests shocking or unacceptable behavior or actions.
an unacceptable	Indicates something that cannot be tolerated or approved.
a disproportionate	Suggests an imbalance or lack of proper relationship between things.

Common Mistakes

• Using "a" instead of "an" before "unreasonable." For example, saying "a unreasonable request" is incorrect; it should be "an unreasonable request."
• Using "unreasonable" as a verb or a noun. It functions as an adjective.
• Incorrectly assuming the phrase is idiomatic and trying to alter it.

The most common mistake is using the indefinite article "a" before a word that begins with a vowel sound, instead of using "an".

Quick-Reference Summary

Expression	Meaning	Grammatical Pattern	Register
an unreasonable	Not guided by or based on good sense	Article + Adjective + Noun	Neutral

FAQs

Can the parts of "an unreasonable" be separated, or must they stay together?

The components of "an unreasonable" generally stay together, functioning as a unit modifying a noun. You can insert adverbs to modify the adjective, like "an extremely unreasonable demand," but you can't arbitrarily separate the article and adjective without affecting the phrase's grammatical correctness.

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What's the difference between "an unreasonable" and its closest alternative, "an excessive"?

While both describe something beyond what's acceptable, "an unreasonable" focuses on a lack of logic or good sense. "An excessive", on the other hand, emphasizes that something goes beyond a normal or acceptable amount or degree.

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How can I correct the common mistake of saying "a unreasonable"?

The simplest way to correct the mistake is to remember the basic rule: use "an" before words that begin with a vowel sound. Since "unreasonable" starts with a vowel sound, the correct form is "an unreasonable", not "a unreasonable."