sob vs soir, What's the Difference?

Which to use

“sob” is a preposition and “soir” is a noun - they look or sound alike but fill different roles in a sentence.

#320
“sob” frequency rank: #47,619
“soir” frequency rank: 47939
confusion score

Side-by-Side Comparison

Feature	sob	soir
Definition	abaixo, em baixo	noite (período entre o anoitecer e a meia-noite)

Where the spellings diverge

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

3 ch

sob

4 ch

soir

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: sob is /ˈsob/ while soir is \swaʁ\. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (preposition vs noun), which is usually the fastest check. Our composite confusion score for this pair is 47939, derived from the frequency rank of both members and their visual similarity.

sob is recorded at frequency rank #320, classified as aprep, pronounced /ˈsob/. soir is at rank #47,619, tagged as anoun, pronounced \swaʁ\.

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 47939, this pair ranks #17,275 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.

Orthographic DNA of sob vs soir

Shared letters: os. Private to "sob": b. Private to "soir": ir.

"sob" · 3 letters · shape CVC · "soir" · 4 letters · shape CVVC

Known mistypes of this pair

soir ← osir · sior · soirr · sori · ssoir

Frequency comparison

sob#320

soir#47,619

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "sob" and "soir" be used interchangeably?

No - they are not even the same part of speech. "sob" is a preposition and "soir" a noun, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "sob" or "soir"?

"sob" is the more common of the two: it sits at frequency rank #320 in our Portuguese list, against #47,619 for "soir". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Remembering sob vs soir

The fastest way to pick the right one every time.

Check the role first: if you need a preposition, it's “sob”; for a noun, it's “soir”.
See each word in full, definition, IPA, etymology and its other confusables. Full “sob” entry
Browse more pairs most likely to be confused. Most confusable