fis vs fog, What's the Difference?

Which to use

“fis” is a verb and “fog” is a noun - they look or sound alike but fill different roles in a sentence.

#16,880
“fis” frequency rank: #46,768
“fog” frequency rank: 63648
confusion score

Side-by-Side Comparison

Feature	fis	fog
Definition	Première personne du singulier du passé simple de faire.	Brouillard, brume.

Where the spellings diverge

Shared letters are muted; the letters that actually set fis and fog apart are highlighted. They share 1 letter in sequence, which is exactly why the eye skips the difference.

3 ch

fis

3 ch

fog

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: fis is \fi\ while fog is \fɔɡ\. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 63648, derived from the frequency rank of both members and their visual similarity.

fis is recorded at frequency rank #16,880, classified as averb, pronounced \fi\. fog is at rank #46,768, tagged as anoun, pronounced \fɔɡ\.

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 63648, this pair ranks #80,909 of 440,172 scored French confusable pairs - among the most confusable pairs.

Orthographic DNA of fis vs fog

Shared letters: f. Private to "fis": is. Private to "fog": go.

"fis" · 3 letters · shape CVC · "fog" · 3 letters · shape CVC

Frequency comparison

fis#16,880

fog#46,768

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "fis" and "fog" be used interchangeably?

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

Which is more common, "fis" or "fog"?

"fis" is the more common of the two: it sits at frequency rank #16,880 in our French list, against #46,768 for "fog". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering fis vs fog

The fastest way to pick the right one every time.

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