radiovsradiumWhat's the difference?

Which to use

“radio” and “radium” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#1,059
“radio” frequency rank
#37,184
“radium” frequency rank
38243
confusion score

Side-by-Side Comparison

Feature radio radium
Definition The technology that allows for the transmission of sound or other signals by modulation of electromagnetic waves. The chemical element (symbol Ra) with an atomic number of 88. It is a soft, shiny and silvery radioactive alkaline earth metal.

Where the eye mixes radio and radium

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence. radio runs 5 letters (CVCVV) against radium's 6 (CVCVVC) - the length gap alone is often enough to separate them once you know to check it.

5 ch
radio
6 ch
radium

Why the eye confuses radio with radium

A purely visual mix-up. radio (/ˈɹeɪdiˌəʊ/) and radium (/ˈɹeɪ.dɪ.əm/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 38243, derived from the frequency rank of both members and their visual similarity.

radio is recorded at frequency rank #1,059, classified as anoun, pronounced /ˈɹeɪdiˌəʊ/. radium is at rank #37,184, tagged as anoun, pronounced /ˈɹeɪ.dɪ.əm/.

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 38243, this pair ranks #287,651 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of radio vs radium

Shared letters: adir. Private to "radio": o. Private to "radium": mu.

"radio" · 5 letters · shape CVCVV  ·  "radium" · 6 letters · shape CVCVVC

Known mistypes of this pair

  • radio ← ardio · raddio · radoi · raido · rdaio · rradio
  • radium ← ardium · raddium · radimu · radiumm · raduim · raidum · rdaium · rradium

Frequently Asked Questions

Can "radio" and "radium" be used interchangeably?
No. They are said differently (/ˈɹeɪdiˌəʊ/ versus /ˈɹeɪ.dɪ.əm/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "radio" or "radium"?
"radio" is the more common of the two: it sits at frequency rank #1,059 in our English list, against #37,184 for "radium". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Eye-level mix-up between "radio" and "radium" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "radio" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "radium" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #287,651 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "radio" and "radium" also get mixed up with nearby pairs, the highest-scored neighbour is "radium vs Rahim". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #287,651 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list