An interjection is a word or phrase that directly expresses an emotion, a reaction, or an attitude. It serves to express surprise, joy, pain, hesitation, or appeal, often with a strong spoken quality. It can appear alone or accompany a complete sentence to nuance its tone, as in Exclamations.

Interjections can take the form of isolated, very short, and autonomous words. Some are simple interjections like ah, oh or eh, while others are phrases like zut alors. In usage, they do not change according to gender or number and thus remain invariable.

TypeType.	FormeForm.	DéfinitionDefinition.	ExempleExample.
SimpleSimple.	ahAh.	Interjection isolée qui marque souvent une prise de conscience ou un apaisement.An isolated interjection that often marks a realization or relief.	Ah, je comprends.Ah, I understand.
LocutionExpression.	zut alorsDarn.	Groupe figé qui exprime une réaction vive, souvent l’agacement ou la contrariété.A fixed expression that expresses a strong reaction, often annoyance or irritation.	Zut alors, c’est dommage.Darn, that’s a pity.
InvariableInvariable.	oufPhew.	Forme qui ne s’accorde ni en genre ni en nombre.A form that does not agree in gender or number.	Ouf, tout va bien.Phew, everything is fine.

Onomatopoeias imitate a sound, a gesture, or a sonic impression. They are often used to give an immediate sensation in speech or writing, and their spelling can vary depending on use, pronunciation, or the intended effect. Their form remains flexible in practice, which explains multiple spellings accepted for the same intention.

TypeType.	FormeForm.	DéfinitionDefinition.	ExempleExample.
BruitSound.	ploufSplash.	Onomatopée qui évoque un objet tombant dans l’eau.An onomatopoeia that evokes an object falling into water.	Plouf, la pierre a disparu.Plouf, the stone has disappeared.
SouffleBreath.	pffPff.	Onomatopée qui traduit la fatigue, le dédain ou le découragement.Onomatopoeia that translates fatigue, disdain, or discouragement.	Pff, quelle journée.Pff, what a day.
RireLaughter.	ha haHa ha.	Suite sonore qui imite un éclat de rire.A sound sequence that imitates a burst of laughter.	Ha ha, c’est drôle.Ha ha, it’s funny.

An interjection is usually autonomous and is placed before or after a full sentence depending on the intended effect. It is often followed by an exclamation mark or a comma, because punctuation helps convey its intensity and its relation to the rest of the sentence. This punctuation also falls under the general principles of Punctuation.

IdéeIdea.	ExempleExample.
Une interjection seule forme souvent une unité expressive autonome.An interjection on its own often forms an autonomous expressive unit.	Oh!Oh.
Une interjection peut précéder une phrase pour annoncer une réaction.An interjection can precede a sentence to announce a reaction.	Ah, je comprends.Ah, I understand.
Une interjection peut suivre une phrase pour ajouter une nuance.An interjection can follow a sentence to add a nuance.	Je viendrai, oui, bien sûr.I will come, yes, of course.

The intonation of the interjection varies with the emotion expressed. It can rise to mark astonishment, the call, or momentum, and fall to signal weariness, resignation, or relief. In writing, this variation is often conveyed by expressive punctuation or by emphatic writing.

IdéeIdea.	ExempleExample.
Une intonation montante exprime souvent l’étonnement ou l’appel.A rising intonation often expresses astonishment or appeal.	Oh? Tu viens déjà?Oh? Are you coming already?
Une intonation descendante exprime souvent la lassitude ou le soulagement.A falling intonation often expresses weariness or relief.	Ouf, enfin terminé.Phew, finally finished.
L’écriture peut accentuer l’émotion pour reproduire l’oral.Writing can intensify emotion to reproduce spoken language.	Aaaah, quelle surprise!Aaaah, what a surprise!

Interjections vary by register, from the most formal to the most informal. Forms like hélas belong to a more elevated usage, while pff or ouf are clearly more informal. Some old or colorful forms, such as sacrebleu, may seem strong, dated, or expressive depending on the context.

RégionRegion.	Mot ou locutionWord or phrase.	Définition régionaleRegional definition.	ExempleExample.
FranceFrance.	hélasAlas.	Interjection soutenue qui exprime le regret ou le malheur.A formal interjection that expresses regret or misfortune.	Hélas, la nouvelle est tardive.Alas, the news is late.
FranceFrance.	pffPff.	Interjection familière qui marque la fatigue, l’agacement ou le doute.A familiar interjection that marks fatigue, annoyance, or doubt.	Pff, il hésite encore.Pff, he hesitates again.
FranceFrance.	oufPhew.	Interjection familière qui exprime le soulagement.A familiar interjection that expresses relief.	Ouf, le train est arrivé.Phew, the train has arrived.
FranceFrance.	sacrebleuGood grief.	Forme archaïque ou colorée qui renforce une réaction vive.An archaic or colorful form that reinforces a vivid reaction.	Sacrebleu, quel bruit!Good grief, what a noise!

The use of interjections also varies across Francophone regions, especially in Quebec and Belgium. Some forms, certain intonations, and certain uses are more frequent there or carry a recognizable local nuance. These differences reflect living French and do not hinder understanding, but they modify the color of the statement.

RégionRegion.	Mot ou locutionWord or phrase.	Définition régionaleRegional definition.	ExempleExample.
QuébecQuebec.	tséYou know.	Marque orale familière qui introduit une précision ou une reprise.A familiar spoken marker that introduces a clarification or a reiteration.	Tsé, je voulais partir tôt.You know, I wanted to leave early.
BelgiqueBelgium.	une foisOne time.	Forme expressive associée à un effet local et souvent orale.An expressive form associated with a local effect and often oral.	Viens une fois, on y va.Come on, let’s go.
QuébecQuebec.	là làThere, there.	Interjection qui peut marquer l’étonnement ou l’insistance selon le contexte.An interjection that can mark astonishment or insistence depending on the context.	Là là, quelle histoire.There, there, what a story.

Interjections are direct tools of affective expression, useful for signaling a reaction without developing a full sentence. They remain invariable, are often placed alone or in support of an utterance, and require punctuation appropriate to their strength. Their value depends on the register, tone, and, depending on the case, regional usages.