Serious vs. Seriously – Which is Correct?

The choice between serious and seriously hinges on their grammatical roles: serious is an adjective, modifying nouns and pronouns, while seriously is an adverb, modifying verbs, adjectives, or other adverbs. Understanding this fundamental distinction is key to using them correctly in sentences.

Serious or Seriously – Which is Correct?

Both serious and seriously are correct American English words, but they serve different functions in a sentence. The core difference lies in their part of speech: serious is an adjective, describing a noun or pronoun, indicating importance, gravity, or earnestness. In contrast, seriously is an adverb, modifying a verb, an adjective, or another adverb, indicating how, to what extent, or in what manner something is done.

The Best Trick to Remember the Difference

To remember the difference, use the “What is it describing?” trick. If the word describes a thing (a noun or pronoun), you need the adjective serious. If the word describes how something is done (a verb), to what extent something is (an adjective), or how another adverb is acting, you need the adverb seriously. Think of it this way: adjectives describe “what kind,” adverbs describe “how.”

Word	Part of Speech	Meaning	Example
Serious	Adjective	Grave, important, earnest, not joking	That’s a serious problem.
Seriously	Adverb	In a serious manner, to a great extent, indeed	He took the challenge seriously.

How to Use Serious

The word serious functions primarily as an adjective, modifying nouns and pronouns. It conveys a sense of gravity, importance, earnestness, or lack of humor. It can describe a situation, a person’s demeanor, a condition, or a threat.

Example 1: The doctor delivered the news with a serious expression.

Example 2: Climate change is a serious issue that requires immediate attention.

Example 3: After the accident, she had a serious injury to her leg.

What are the different forms of Serious?

As an adjective, serious has comparative and superlative forms to indicate degrees of intensity:

• Positive: serious (e.g., a serious mistake)
• Comparative: more serious (e.g., a more serious mistake)
• Superlative: most serious (e.g., the most serious mistake)

Etymology of the word Serious

The word “serious” comes from the Late Latin seriosus, meaning “grave, weighty,” which itself is derived from the Latin serius. It entered English in the late 16th century, retaining its core meaning of being earnest, solemn, or important.

How to Use Seriously

The word seriously functions as an adverb, modifying verbs, adjectives, or other adverbs. It describes how an action is performed, to what extent something is true, or adds emphasis. It can indicate a lack of joking, deep concern, or a significant degree.

Example 1: She considered his proposal seriously before giving her answer.

Example 2: The new policy will seriously impact small businesses.

Example 3: Are you seriously suggesting we cancel the entire project?

What are the different forms of Seriously?

As an adverb, seriously also has comparative and superlative forms, typically formed with “more” and “most,” as it is a multi-syllable adverb ending in -ly:

• Positive: seriously (e.g., He spoke seriously.)
• Comparative: more seriously (e.g., She took the exam more seriously than he did.)
• Superlative: most seriously (e.g., Of all the candidates, she prepared most seriously.)

Etymology of the word Seriously

The adverb “seriously” is formed by adding the suffix “-ly” to the adjective “serious.” This suffix is commonly used in English to transform adjectives into adverbs, indicating “in a [adjective] manner.” Its etymological roots, therefore, mirror those of “serious,” tracing back to the Latin serius.

Related Concepts

Understanding the broader grammatical categories of adjectives and adverbs is fundamental to correctly distinguishing between words like “serious” and “seriously.”

• Adjectives: Words that describe or modify nouns and pronouns. They answer questions like “which one?”, “what kind?”, or “how many?”. Examples: happy, tall, blue, serious.
• Adverbs: Words that describe or modify verbs, adjectives, or other adverbs. They answer questions like “how?”, “when?”, “where?”, “to what extent?”, or “why?”. Many adverbs are formed by adding “-ly” to an adjective. Examples: happily, quickly, very, seriously.

Examples from Media and Literature

• “Why so serious?” – The Joker in The Dark Knight (2008), using “serious” as an adjective to describe “so”.
• “I shall be seriously displeased if you don’t do as I ask.” – From J.K. Rowling’s Harry Potter and the Chamber of Secrets, where “seriously” modifies the adjective “displeased.”
• “This is not a drill; this is a serious situation.” – A common phrase in emergency broadcasts, using “serious” to describe “situation.”
• “He thought seriously about the implications of his actions.” – From a news article discussing a political decision, “seriously” modifies the verb “thought.”
• “Are you seriously going to wear that to the formal event?” – A line from a contemporary novel, “seriously” emphasizes the question, modifying the verb “going.”

Practice Exercises

Choose the correct word to complete the sentence.

1. The manager took the employee’s concerns very (serious / seriously).
2. She has a (serious / seriously) talent for playing the piano.
3. Don’t take his jokes too (serious / seriously); he’s just being playful.
4. The economy is facing some (serious / seriously) challenges this year.
5. He paused, considering the matter (serious / seriously) before replying.

Answer Key

1. seriously
2. serious
3. seriously
4. serious
5. seriously

Serious Synonyms

Synonym	Definition
Grave	Very serious and important; giving cause for alarm.
Solemn	Formal and dignified; not cheerful or smiling.
Earnest	Resulting from or showing sincere and intense conviction.
Critical	Having a decisive importance in the success or failure of something.
Weighty	Of great importance or influence.

Seriously Synonyms

Synonym	Definition
Gravely	In a serious or solemn manner.
Earnestly	With sincere and intense conviction; with great seriousness.
Significantly	In a sufficiently great or important way as to be worthy of attention.
Indeed	Used to emphasize a statement or response confirming something already suggested.
Profoundly	To a great depth or extent; intensely.

Frequently Asked Questions

Question 1: Can “seriously” be used informally as an exclamation?
Yes, “seriously” is often used informally as an exclamation to express disbelief, exasperation, or to ask if someone is being truthful. For example, “Seriously? You forgot my birthday again?”

Question 2: Is it ever correct to use “serious” to modify a verb?
No, it is generally incorrect to use “serious” (the adjective) to modify a verb. You should use the adverb “seriously” for that purpose. For example, instead of “He takes his job serious,” it should be “He takes his job seriously.”

Question 3: How does the meaning of “serious” change when paired with different nouns?
The meaning of “serious” can subtly shift depending on the noun it modifies. For example, a “serious illness” implies gravity and potential danger, a “serious student” implies diligence and earnestness, and a “serious joke” is an oxymoron, highlighting the word’s meaning of “not joking.”

Conclusion

Mastering the distinction between serious and seriously is a matter of understanding their fundamental grammatical roles: serious is an adjective describing nouns, while seriously is an adverb modifying verbs, adjectives, or other adverbs. By applying the “What is it describing?” trick, you can confidently choose the correct word. A strong grasp of these nuances not only improves your writing clarity but also enhances your professional communication, ensuring your messages are conveyed precisely as intended.