Sérieux (or its feminine form, sérieuse) is the most common way to say “serious” in French. But just like in English, there are several other options to convey different shades of meaning. Whether you're describing a solemn situation, a deep-thinking person, or a critical matter, having a variety of words will make your French sound much more natural and precise. Let's explore 9 different ways to say “serious” in French and when to use them!

The standard 'serious' – sérieux/sérieuse

The standard 'serious' – sérieux/sérieuse

Sérieux/sérieuse is the most common and versatile adjective for 'serious' in French.

This adjective must agree in gender and number with the noun it modifies. Here's how it changes:sérieux - masculine singular (e.g., un homme sérieux - a serious man)sérieuse - feminine singular (e.g., une femme sérieuse - a serious woman)sérieux - masculine plural (e.g., des problèmes sérieux - serious problems, des hommes sérieux - serious men)sérieuses - feminine plural (e.g., des discussions sérieuses - serious discussions, des femmes sérieuses - serious women)

You can use sérieux/sérieuse in a wide range of situations, from describing a person's character to the gravity of a situation, making it a highly adaptable word.

While primarily meaning 'serious', it can convey different shades like 'diligent', 'reliable', 'important', or 'severe' depending on the context.

The meaning of sérieux/sérieuse often depends on whether it describes a person or a thing. When applied to a person, it usually means 'earnest', 'responsible', or 'not joking'. When applied to a thing or situation, it can mean 'important', 'grave', or 'significant'.

For instance, if you say Il est très sérieux, you're likely describing someone who is earnest and responsible. However, C'est un problème sérieux means it's an important or grave problem. In informal contexts, Tu es sérieux? (masculine) or Tu es sérieuse? (feminine) can mean 'Are you serious?' in disbelief.

Always remember to ensure the adjective agrees with the noun it describes. A common mistake for learners is to use the masculine singular form for all genders and numbers, so pay close attention to the endings!

Fortunately, discerning the exact nuance of sérieux/sérieuse is usually straightforward through context. The surrounding words and the overall situation will guide your understanding, just like in English with the word 'serious'.

Beyond its basic meaning, sérieux is also used in common expressions. For example, sans rire, c'est sérieux means 'no kidding, it's serious', and le sérieux (as a noun) refers to 'seriousness' or 'diligence'. You might also hear prendre quelque chose au sérieux, meaning 'to take something seriously'.

💡 * Elle est très sérieuse dans son travail. (She is very diligent in her work.)* C'est une question sérieuse. (It's a serious question.)* Ne sois pas si sérieux, c'est une blague ! (Don't be so serious, it's a joke!)* Nous avons eu une discussion sérieuse hier soir. (We had a serious discussion last night.)* Il a des problèmes de santé sérieux. (He has serious health problems.)

The 'grave' or 'severe' – grave

The French adjective grave is a highly versatile word that translates to “serious” or “severe” in English. It's used across a wide range of contexts, from describing health conditions to the gravity of a situation or even a person's demeanor.

One of the most common uses of grave is to describe something serious or severe in a medical or physical sense. This can refer to an illness, an injury, or a patient's condition.

Grave also frequently describes the seriousness or severity of a situation, a problem, a mistake, or an event. It conveys a sense of weight, importance, or potential negative consequences.

Beyond physical or situational gravity, grave can also characterize a person's tone, expression, or demeanor as serious, solemn, or even somber. It suggests a lack of lightheartedness.

As an adjective, grave agrees in number with the noun it modifies. However, it is invariable in gender. This means it remains grave for both masculine and feminine singular nouns, and becomes graves for both masculine and feminine plural nouns.

Perhaps one of its most common uses in everyday conversation is in the phrase Ce n'est pas grave (It's not serious / It's okay / Never mind), which is a very useful way to reassure someone. Understanding grave is key to grasping nuances in French communication.

💡 * Son état est grave. (His condition is serious.)

• C'est une erreur grave. (It's a serious mistake.)
• Il a une voix grave. (He has a deep/serious voice.)
• Ne t'inquiète pas, ce n'est pas grave. (Don't worry, it's not serious/it's okay.)
• Les conséquences pourraient être graves. (The consequences could be severe.)

The 'strict' or 'stern' – sévère

The French adjective sévère directly translates to "strict" or "stern" in English. It's a common word you'll encounter when describing people, rules, or even judgments.

As an adjective, sévère modifies nouns. Interestingly, it does not change its form for gender. It remains sévère for both masculine and feminine singular nouns. It only changes for number, becoming sévères for plural nouns (masculine or feminine).

When applied to people, sévère implies someone who is demanding, unyielding, or not easily swayed. For instance, a professeur sévère (strict teacher) or a parent sévère (stern parent) would be someone who enforces rules rigidly and expects high standards.

Beyond individuals, sévère can also describe rules, laws, or punishments that are harsh, rigorous, or unforgiving. A règlement sévère (strict regulation) or a jugement sévère (harsh judgment) indicates a lack of leniency.

The term can extend to describe a style or appearance that is austere, unadorned, or severe, such as un style vestimentaire sévère (a severe dress style). It consistently conveys a sense of rigor, seriousness, or a lack of softness across various contexts.

💡 * Le professeur est très sévère avec ses élèves. (The teacher is very strict with her students.)* Les règles de l'examen sont extrêmement sévères. (The exam rules are extremely strict.)* Elle a un regard sévère qui intimide un peu. (She has a stern look that's a bit intimidating.)* Il a reçu une punition sévère pour sa faute. (He received a severe punishment for his mistake.)* Malgré son air sévère, il est très juste. (Despite his stern appearance, he is very fair.)

The 'diligent' or 'earnest' – appliqué/appliquée

The French adjective appliqué (masculine) or appliquée (feminine) translates to “diligent,” “earnest,” “hard-working,” or “conscientious.” It describes someone who puts a lot of effort and care into what they do.

As an adjective, appliqué/appliquée must agree in gender and number with the noun it modifies. The masculine singular form is appliqué, feminine singular is appliquée, masculine plural is appliqués, and feminine plural is appliquées.

This term carries a strong positive connotation, often used to praise someone for their dedication and thoroughness. It implies a methodical and serious approach to a task or learning.

While primarily used to describe people (e.g., a diligent student), appliqué can also refer to the quality of work or effort itself, suggesting careful and meticulous execution.

💡 * Elle est une élève très appliquée. (She is a very diligent student.)

• Il travaille toujours avec un esprit appliqué. (He always works with an earnest spirit.)
• Les enfants appliqués ont bien réussi leur examen. (The diligent children did well on their exam.)
• C'est un travail appliqué et soigné. (It's a diligent and neat work.)
• Soyez appliqués dans vos études. (Be diligent in your studies.)

The 'deep' or 'profound' – profond/profonde

The 'deep' or 'profound' – profond/profonde

The French adjective profond (masculine) and profonde (feminine) translates to 'deep' or 'profound' in English, encompassing both physical and abstract dimensions.

As an adjective, profond must agree in gender and number with the noun it modifies. For example, un lac profond (a deep lake) but une rivière profonde (a deep river).

Beyond physical depth, profond/profonde is frequently used to describe abstract concepts like thoughts, emotions, or knowledge. It conveys a sense of intensity, seriousness, or intellectual depth, similar to 'profound' in English. Think of une pensée profonde (a profound thought) or une joie profonde (a deep joy).

Literally, it refers to a significant vertical distance from a surface downwards. This can apply to bodies of water, holes, sleep, or even a voice. For instance, un puits profond (a deep well) or un sommeil profond (a deep sleep).

Its versatility allows it to express a wide range of 'depths,' from the tangible to the intellectual, making it a crucial word for describing complex ideas and physical attributes in French.

💡 * Le lac est très profond à cet endroit. (The lake is very deep at this spot.)

• Elle a des pensées très profondes sur la vie. (She has very profound thoughts about life.)
• Il a pris une profonde inspiration avant de parler. (He took a deep breath before speaking.)
• C'est une question profonde qui nécessite beaucoup de réflexion. (It's a profound question that requires a lot of thought.)
• J'ai eu un sommeil profond la nuit dernière. (I had a deep sleep last night.)

The 'solemn' or 'ceremonial' – solennel/solennelle

The French adjective solennel (masculine singular) and solennelle (feminine singular) translates most directly to “solemn,” “ceremonial,” or “formal.” It conveys a sense of gravity, importance, and often a lack of lightheartedness.

This adjective is frequently used to describe official events, ceremonies, or declarations that are conducted with great seriousness and adherence to protocol. Think of state occasions, religious rites, or important legal proceedings.

Beyond just events, solennel can also characterize a mood, an expression, or a moment that is particularly serious, weighty, or deeply significant. It implies a sense of profound respect or contemplation.

As an adjective, solennel must agree in gender and number with the noun it modifies. Remember: solennel (m.s.), solennelle (f.s.), solennels (m.p.), and solennelles (f.p.).

The core idea behind solennel/solennelle is to emphasize the gravity and significance of something, marking it as distinct from everyday or casual matters. It's about a moment or act that demands respect and attention.

💡 * Une cérémonie de mariage était très solennelle. (A wedding ceremony was very solemn.)

• Le président a fait une déclaration solennelle à la nation. (The president made a solemn declaration to the nation.)
• Son regard était solennel, montrant sa préoccupation. (His gaze was solemn, showing his concern.)
• Ils ont prononcé des vœux solennels. (They pronounced solemn vows.)
• Elle portait une tenue solennelle pour l'occasion. (She wore a ceremonial outfit for the occasion.)

The 'level-headed' or 'thoughtful' – pondéré/pondérée

The French adjective pondéré (masculine) or pondérée (feminine) describes someone who is level-headed, thoughtful, balanced, or prudent.

This word implies a calm and measured approach, often someone who takes time to consider all aspects before acting or speaking, avoiding impulsivity. It suggests wisdom and good judgment.

As an adjective, pondéré must agree in gender and number with the noun it modifies. For example, you would say un homme pondéré (a level-headed man) and une femme pondérée (a level-headed woman).

💡 * Il est toujours très pondéré dans ses décisions. (He is always very level-headed in his decisions.)

• Elle a donné une réponse pondérée après mûre réflexion. (She gave a thoughtful answer after careful consideration.)
• Nous avons besoin de leaders pondérés pour naviguer cette crise. (We need balanced leaders to navigate this crisis.)
• Son analyse était pondérée et juste. (His analysis was balanced and fair.)

The 'rigorous' or 'thorough' – rigoureux/rigoureuse

The French adjective rigoureux/rigoureuse translates to “rigorous,” “thorough,” “strict,” or “demanding” in English.

This adjective describes something or someone characterized by strictness, precision, and adherence to rules or high standards. It's often used in academic, scientific, or professional contexts to denote meticulousness and exactness.

As an adjective, rigoureux (masculine singular) changes to rigoureuse (feminine singular), rigoureux (masculine plural), and rigoureuses (feminine plural) to agree with the noun it modifies.

You'll frequently encounter it describing methods, analyses, research, or individuals who are very disciplined in their approach. For instance, a méthode rigoureuse is a rigorous method.

💡 * Son analyse était très rigoureuse. (His analysis was very thorough.)

• Il faut une approche rigoureuse pour ce projet. (A rigorous approach is needed for this project.)
• Elle est connue pour sa logique rigoureuse. (She is known for her rigorous logic.)
• Les règles de sécurité sont rigoureuses ici. (The safety rules are strict here.)
• Nous avons besoin de résultats rigoureux et précis. (We need rigorous and precise results.)

The 'austere' or 'somber' – austère

The French adjective austère directly translates to 'austere' or 'somber' in English. It is a versatile word used to describe various aspects, from personalities to environments, often implying a lack of luxury, warmth, or ornamentation.

When describing a person, austère suggests someone who is severe, strict, or self-disciplined, often abstaining from pleasures or luxuries. It can also refer to a mode de vie austère (austere lifestyle) marked by simplicity and rigor.

For places, objects, or styles, austère implies a lack of decoration, warmth, or comfort. Think of a bâtiment austère (austere building) with plain architecture, or une décoration austère (austere decoration) that is minimalistic and stark.

Beyond physical descriptions, austère can also characterize something as strict, severe, or rigorous. For instance, des mesures budgétaires austères (austere budgetary measures) refer to strict financial policies, often implying cutbacks or frugality.

💡 * Son visage était austère, mais son cœur était bon. (His face was somber/stern, but his heart was good.)

• Elle mène une vie très austère, sans aucun superflu. (She leads a very austere life, without any superfluity.)
• Le monastère avait une architecture austère et imposante. (The monastery had an austere and imposing architecture.)
• Le gouvernement a annoncé des réformes économiques austères. (The government announced austere economic reforms.)
• La pièce était austère, meublée seulement d'un lit et d'une chaise. (The room was austere, furnished only with a bed and a chair.)

Are there other ways to say 'serious' in French?

Are there other ways to say “serious” in French?

Our list features the most common ways to say “serious” in French. But there are other terms, from old-fashioned ones, to regional ones, to up-and-coming slang ones this middle-aged author might not even be aware of!

You can also do an online search for “comment dire sérieux en ___” followed by a specific Francophone country or region.

You might find some interesting synonyms for sérieux on this list. Of course, make sure to check a word’s definition and try to see it used in context before you use it.

Pay attention as you read, watch, and listen to things in French — you may discover different ways to talk about seriousness or describe serious situations and people.

And if you’re looking for ways to talk about different nuances of 'serious', or words about gravity and earnestness in French, the WordReference entry for sérieux is a great place to start!

I hope you found this article helpful. Here’s what I think is a perfect quote to finish it with, courtesy of Victor Hugo: La gravité n'est qu'un mystère du corps inventé pour cacher les défauts de l'esprit. (Gravity is but a mystery of the body invented to hide the defects of the mind.)