césium

\se.zjɔm\

/\se.zjɔm\/ noun

By · According to Wiktionary data (CC BY-SA) ·

The verdict

“césium” is uncommon French (frequency #59,208 among 257,141 “C” headwords), classed as a noun. The kind of spelling people second-guess.

#59,208
frequency rank, French
257,141
“C” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Élément chimique de numéro atomique 55 et de symbole Cs qui fait partie de la série chimique des métaux alcalins.

Key facts for césium
PropertyValue
Headwordcésium
LanguageFrench
Part of speechNoun
IPA\se.zjɔm\
Letters6
Frequency rank#59,208
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “césium” sits in French frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). césium lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Rare enough to double-check

césium is uncommon French at frequency #59,208 among 257,141 “C” headwords, classed as anoun, transcribed \se.zjɔm\. Rarity is why readers land here mid-draft. 2 senses are on record.

No generated misspelling entries exist for césium in our index, a straightforward case of a spelling with little room for common typos. It is not paired with a close-neighbour confusable in our dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

No documented word history exists for this headword, so its spelling is easiest explained by how it's pronounced rather than where it came from. The correct French form is césium, spelled C-É-S-I-U-M.

Definition

  1. 1
    Élément chimique de numéro atomique 55 et de symbole Cs qui fait partie de la série chimique des métaux alcalins.
  2. 2
    Corps simple de cet élément, alcalin argent-doré.

This word in other languages

caesium(English)cesio(Español)Caesium(Deutsch)césio(Português)

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 French corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "césium"?
"césium" is spelled C-É-S-I-U-M. The IPA pronunciation is \se.zjɔm\.
What does "césium" mean?
As a noun, "césium" means: Élément chimique de numéro atomique 55 et de symbole Cs qui fait partie de la série chimique des métaux alcalins.
How do you pronounce "césium"?
The IPA (International Phonetic Alphabet) transcription for "césium" is \se.zjɔm\. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What language does "césium" come from?
"césium" is a French word. PlainSpell covers definitions, pronunciations, and spelling data across English, Spanish, Portuguese, French, and German.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “césium”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct French spelling is C-É-S-I-U-M - every other letter order is a misspelling in standard orthography.
  • Say it as \se.zjɔm\ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more French words and confusable pairs in the same reference. French words

Other uncommon French words near this rank

Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

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

Source: FrequencyWords open word-frequency list