The most common and direct way to say “sister” in French is sœur. But what about nicknames or terms of endearment? Just like in English, French offers a variety of ways to refer to your sister, each with its own nuance and level of affection.

Whether you're talking about your biological sister, a stepsister, or even a close friend who feels like a sister, knowing these different terms will help you sound more like a native speaker and better understand the relationships around you.

Let's dive into 9 ways to say “sister” in French!

The standard 'sister' – sœur

The standard and most common word for 'sister' in French is sœur.

Sœur is a feminine noun, so it is always used with feminine articles like la (the) or une (a/an). For example, you would say la sœur (the sister) or une sœur (a sister).

To talk about more than one sister, you simply add an 's' to make the plural form: sœurs. For example, mes sœurs (my sisters) or les deux sœurs (the two sisters).

French has specific and very common terms to distinguish between older and younger sisters, which is a key difference from English:

grande sœur means 'older sister' (literally 'big sister').
petite sœur means 'younger sister' (literally 'little sister').

To show possession, you use feminine possessive adjectives. For example, ma sœur means 'my sister', ta sœur is 'your sister', and sa sœur means 'his/her sister'.

It's also important to know that sœur is the word for 'nun' or 'sister' in a religious context. For instance, Sœur Emmanuelle was a famous Franco-Belgian nun. The context almost always makes it clear whether you're talking about a family member or a member of a religious order.

💡 * Ma sœur habite à Lyon. (My sister lives in Lyon.)

J'ai deux sœurs et un frère. (I have two sisters and one brother.)

Comment s'appelle ta grande sœur ? (What is your older sister's name?)

Il a offert un cadeau à sa petite sœur pour son anniversaire. (He gave a gift to his little sister for her birthday.)

Les sœurs Dupont sont toutes les deux avocates. (The Dupont sisters are both lawyers.)

The affectionate 'sis' – sœurette

The affectionate 'sis' – sœurette

A common way to show affection to a sister in French is by using the diminutive term sœurette. It’s the direct equivalent of calling someone 'sis' or 'little sis' in English.

The word is formed by taking sœur (sister) and adding the suffix -ette. This suffix is often used in French to make something sound smaller, cuter, or more endearing.

While it literally translates to 'little sister', sœurette is used more broadly as a term of endearment for any sister, regardless of age. It implies a close, loving, and informal relationship.

You would use this term in casual, private conversations with your family. For example, you might start a text message with Salut sœurette ! (Hi sis!). It’s a warm and personal term, not one you would use in a formal context.

💡 * Qu'est-ce que tu fais ce soir, ma sœurette ? (What are you doing tonight, my sis?)

J'ai un cadeau pour ma sœurette. (I have a gift for my little sister.)

Ma sœurette est ma meilleure amie. (My sis is my best friend.)

Allez, sœurette, ne sois pas triste ! (Come on, sis, don't be sad!)

The informal 'sis' – frangine

For a very informal, slang way to say 'sister,' you can use frangine. It's a term of endearment and familiarity, much like saying 'sis' in English.

This word is part of French slang (l'argot) and is considered very familiar. You would use it in casual conversations with friends and family, but you should avoid it in formal settings. It is the informal equivalent of the standard word sœur (sister).

The masculine version of this term is frangin, which is a slang word for 'brother' (frère). It carries the same casual and affectionate tone, similar to 'bro' in English.

You'll often hear frangine and frangin used when people talk about their siblings in a relaxed way. For instance, you might ask a friend, "Comment va ta frangine ?" (How's your sis?).

The plural forms are simple and regular: frangines for multiple sisters and frangins for multiple brothers or a mixed-gender group of siblings.

💡 * Ma frangine arrive ce week-end.

Qu'est-ce que tu as offert à ta frangine pour son anniversaire ?

J'ai un frangin et deux frangines.

Salut ma frangine, ça va ?

The 'big sister' – grande sœur

The standard French term for 'big sister' or 'older sister' is grande sœur.

Literally translating to 'big sister,' the phrase combines grande (big/great) and sœur (sister). In this context, grande specifically refers to being older in age, not larger in physical size.

Because sœur is a feminine noun, the adjective grande is used in its feminine form. This demonstrates the core French grammar rule of adjective-noun agreement in gender and number.

Grande sœur is the most common and direct way to refer to an older female sibling in everyday French, whether you are talking about your own sister or someone else's.

💡 * Ma grande sœur habite à Paris. (My big sister lives in Paris.)

J'ai demandé conseil à ma grande sœur. (I asked my big sister for advice.)

C'est la grande sœur de mon meilleur ami. (She is my best friend's big sister.)

Ma grande sœur et moi sommes très proches. (My big sister and I are very close.)

The 'little sister' – petite sœur

The term petite sœur is the direct and most common way to refer to a 'little sister' in French.

It literally translates to 'little sister,' combining petite (the feminine form of 'little' or 'small') and sœur ('sister').

This phrase is a clear example of French gender agreement. Because sœur is a feminine noun, the adjective that describes it (petit) must also take its feminine form, becoming petite.

Petite sœur is a standard term used across all levels of formality, from official documents to casual family conversations. It always refers to a younger female sibling.

💡 * Ma petite sœur adore dessiner.

Je vais chercher ma petite sœur à l'école.

Comment s'appelle ta petite sœur ?

Il est très protecteur envers sa petite sœur.

The 'half-sister' – demi-sœur

In French, the term for 'half-sister' is demi-sœur. This is a straightforward, literal translation used to describe a female sibling with whom you share only one biological parent.

The word is composed of two parts: demi, meaning 'half', and sœur, meaning 'sister'. They are joined by a hyphen to form a single compound noun, demi-sœur.

The term is feminine because sœur is a feminine noun. The masculine equivalent is demi-frère ('half-brother'). For the plural, you add an 's' only to the noun part: des demi-sœurs or des demi-frères.

Unlike slang, demi-sœur is a standard and neutral term. It is used in all registers of French, from everyday conversation with friends to official or legal documents. There is no other common or informal way to express this relationship.

💡 * J'ai une demi-sœur qui est plus jeune que moi.

Ma mère s'est remariée et maintenant j'ai un demi-frère et une demi-sœur.

Elle s'entend très bien avec sa demi-sœur.

Combien de demi-sœurs as-tu ?

The 'stepsister' – belle-sœur

In French, the term belle-sœur is a versatile word used for female in-laws and step-family. It most commonly translates to either 'stepsister' or 'sister-in-law'.

When used to mean 'stepsister', belle-sœur refers to the daughter of your stepparent. For example, if your father remarries a woman who has a daughter, that daughter is your belle-sœur.

The term also means 'sister-in-law'. This can be either your spouse's sister or your brother's wife. The specific relationship is usually clear from the context of the conversation.

💡 * Ma nouvelle belle-sœur vient vivre avec nous la semaine prochaine. (My new stepsister is coming to live with us next week.)

J'ai acheté un cadeau pour ma belle-sœur, la femme de mon frère. (I bought a gift for my sister-in-law, my brother's wife.)

Ma belle-sœur, la sœur de mon mari, est avocate. (My sister-in-law, my husband's sister, is a lawyer.)

The 'sister-in-law' – also belle-sœur

The 'sister-in-law' – also belle-sœur

Just like its masculine counterpart (beau-frère), belle-sœur is the French term for 'sister-in-law'. The literal translation is 'beautiful sister', which mirrors the structure for other in-laws.

This term has a dual meaning, which can sometimes be confusing. It refers to either your spouse's sister or your brother's wife. The specific relationship is usually understood from the context of the conversation.

The plural form is belles-sœurs. It's important to note that for this compound noun, both words are made plural: belle becomes belles and sœur becomes sœurs.

💡 * Ma belle-sœur, la femme de mon frère, est médecin. (My sister-in-law, my brother's wife, is a doctor.)

J'ai une très bonne relation avec la sœur de ma femme, ma belle-sœur. (I have a very good relationship with my wife's sister, my sister-in-law.)

Mes belles-sœurs viennent dîner ce soir. (My sisters-in-law are coming for dinner tonight.)

The 'sister' in a religious context (nun) – ma sœur

In French, the word for a biological sister, sœur, is also the term used for a nun. To refer to a nun, you would say une sœur (a sister/nun). The context of the conversation—whether you're talking about family or a religious order—makes the meaning clear.

When addressing a nun directly and respectfully, it is common to call her ma sœur, which literally translates to 'my sister'. This is the equivalent of addressing a nun as 'Sister' in English.

The formal title for a nun is Sœur (capitalized) followed by her religious name, much like in English. For example, one would refer to Sœur Thérèse or Sœur Marie. This is used in both spoken and written French to refer to a specific nun.

💡 *Bonjour ma sœur, puis-je vous poser une question ? (Hello Sister, may I ask you a question?)
*La chorale est dirigée par Sœur Agnès. (The choir is led by Sister Agnès.)
*Elle a décidé de devenir une sœur et de rejoindre le couvent. (She decided to become a nun and join the convent.)
*Ma sœur (my biological sister) a rendu visite à une sœur (a nun) à l'église. (My sister visited a nun at the church.)

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

This list covers the most common and essential ways to say 'sister' in French. However, French is a rich language with many nuances. You'll find other terms, including regional variations, endearing nicknames, and modern slang that young people might use.

For a deeper dive, you can do an online search for phrases like “comment dire sœur en verlan” (how to say sister in French back-slang) or by looking into the specific dialects of Francophone regions.

When you discover a new synonym for sœur, it's a great idea to check its definition and observe how it's used in context. Some terms might be very informal or specific to a certain age group or social circle.

The best way to learn these subtleties is through immersion. As you watch French movies, listen to music, or read books, pay close attention to how characters talk about their sisters and female siblings.

If you're curious about related vocabulary, like words for 'sisterhood' or 'sibling,' a great resource is the WordReference page for sœur. It often provides helpful context and compound phrases.

I hope this guide has been helpful in your French learning journey. To end, here is a beautiful quote from the celebrated French author Victor Hugo: Une sœur est un peu de l'enfance qui ne peut jamais se perdre. (A sister is a little bit of childhood that can never be lost.)

'9 ways to say "sister" in French'