rad vs roi, What's the Difference?

Which to use

“rad” is a symbol and “roi” is a noun - they look or sound alike but fill different roles in a sentence.

#28,705
“rad” frequency rank: #547
“roi” frequency rank: 29252
confusion score

Side-by-Side Comparison

Feature	rad	roi
Definition	Symbole du radian, unité de mesure d’angle plan du Système international (SI).	Titre porté par celui qui règne sur un peuple, un État, en particulier un État monarchique, et qui tient sa fonction de l’hérédité ou de l’élection ; celui qui est à la tête d’un royaume.

Letter map: rad vs roi

Shared letters muted; letters that set rad and roi apart highlighted. Shared run: 1.

3 ch

rad

3 ch

roi

Grammar separator: rad vs roi

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: rad is asymbol and roianoun. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 29252, derived from the frequency rank of both members and their visual similarity.

rad is recorded at frequency rank #28,705, classified as asymbol. roi is at rank #547, tagged as anoun, pronounced \ʁwa\.

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 29252, this pair ranks #317,832 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of rad vs roi

Shared letters: r. Private to "rad": ad. Private to "roi": io.

"rad" · 3 letters · shape CVC · "roi" · 3 letters · shape CVV

Frequently Asked Questions

Is swapping "rad" for "roi" ever safe?

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

Which is more common, "rad" or "roi"?

"roi" is the more common of the two: it sits at frequency rank #547 in our French list, against #28,705 for "rad". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Useful next steps

You've compared "rad" and "roi". Here's where to go from here.

Full dictionary entry for "rad" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "roi" - compare definitions side by side with the headword page. Word entry
This pair ranks #317,832 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
"rad" and "roi" also get mixed up with nearby pairs, the highest-scored neighbour is "rad vs RAMQ". Nearby pair

Confusion rank #317,832 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.