sœur vs sir, What's the Difference?

Which to use

“sœur” and “sir” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#1,380
“sœur” frequency rank: #5,610
“sir” frequency rank: 6990
confusion score

Side-by-Side Comparison

Feature	sœur	sir
Definition	Femme ou fille, ayant le même père et la même mère que la personne considérée. Si un seul des parents est commun, c’est une demi-sœur.	Titre pour un chevalier, placé devant son prénom avec ou sans son nom de famille, mais non pas devant seulement son nom de famille.

Where the spellings diverge

Shared letters are muted; the letters that actually set sœur and sir apart are highlighted. They share 2 letters in sequence, which is exactly why the eye skips the difference.

4 ch

sœur

3 ch

sir

Spelling & Dictionary Insight

A purely visual mix-up. sœur (\sœʁ\) and sir (\ˈsɝ\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 6990, derived from the frequency rank of both members and their visual similarity.

sœur is recorded at frequency rank #1,380, classified as anoun, pronounced \sœʁ\. sir is at rank #5,610, tagged as anoun, pronounced \ˈsɝ\.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 6990, this pair ranks #424,595 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of sœur vs sir

Shared letters: rs. Private to "sœur": uœ. Private to "sir": i.

"sœur" · 4 letters · shape CVVC · "sir" · 3 letters · shape CVC

Frequency comparison

sœur#1,380

sir#5,610

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "sœur" and "sir" be used interchangeably?

No. They are said differently (\sœʁ\ versus \ˈsɝ\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.

Which is more common, "sœur" or "sir"?

"sœur" is the more common of the two: it sits at frequency rank #1,380 in our French list, against #5,610 for "sir". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering sœur vs sir

The fastest way to pick the right one every time.

Read both glosses above and match the meaning you intend, only context separates this pair.
See each word in full, definition, IPA, etymology and its other confusables. Full “sœur” entry
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