semvssimConfusable pair

Quick tell: sem is a preposition, sim is an adverb, so they fill different roles in a sentence.

Which to use

“sem” is a preposition and “sim” is an adverb - they look or sound alike but fill different roles in a sentence.

#69
“sem” frequency rank
#147
“sim” frequency rank
216
confusion score

Side-by-Side Comparison

Feature sem sim
Definition indicativa de carência ou ausência exprime afirmação, acordo, aprovação, permissão ou consentimento

Where the eye mixes sem and sim

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

3 ch
sem
3 ch
sim

Visual trap between sem and sim

These two trip readers on the page rather than in the ear: sem is /sɐ̃j̃/ while sim is /ˈsĩ/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - e in “sem” becomes i in “sim”, and the parts of speech differ too (preposition vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 216, derived from the frequency rank of both members and their visual similarity.

sem is recorded at frequency rank #69, classified as aprep, pronounced /sɐ̃j̃/. sim is at rank #147, tagged as anadv, pronounced /ˈsĩ/.

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 216, this pair ranks #75,418 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of sem vs sim

Shared letters: ms. Private to "sem": e. Private to "sim": i.

"sem" · 3 letters · shape CVC  ·  "sim" · 3 letters · shape CVC

Frequently Asked Questions

Do "sem" and "sim" mean the same thing in a sentence?
No - they are not even the same part of speech. "sem" is a preposition and "sim" an adverb, so a sentence built for one is usually ungrammatical with the other.
In ordinary Portuguese text, does "sem" or "sim" show up more?
"sem" is the more common of the two: it sits at frequency rank #69 in our Portuguese list, against #147 for "sim". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "sem" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sim" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #75,418 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "sem" and "sim" also get mixed up with nearby pairs, the highest-scored neighbour is "Sau vs sim". Nearby pair

Confusion rank #75,418 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list