CD4 vs cup, What's the Difference?

Which to use

“CD4” and “cup” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#39,729
“CD4” frequency rank: #805
“cup” frequency rank: 40534
confusion score

Side-by-Side Comparison

Feature	CD4	cup
Definition	A glycoprotein found on the surface of helper T cells and several other types of immune cells.	A concave vessel for drinking, usually made of opaque material (as opposed to a glass) and with a handle.

Letter map: CD4 vs cup

Shared letters muted; letters that set CD4 and cup apart highlighted. Shared run: 1.

3 ch

CD4

3 ch

cup

Spelling & dictionary notes on CD4 vs cup

CD4 and cup are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 40534, derived from the frequency rank of both members and their visual similarity.

CD4 is recorded at frequency rank #39,729, classified as anoun. cup is at rank #805, tagged as anoun, pronounced /kʌp/.

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 40534, this pair ranks #266,683 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of CD4 vs cup

Shared letters: c. Private to "CD4": d. Private to "cup": pu.

"CD4" · 2 letters · shape CC · "cup" · 3 letters · shape CVC

Frequently Asked Questions

Can "CD4" and "cup" be used interchangeably?

No. They share most of their letters but differ in 2 positions, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.

Which is more common, "CD4" or "cup"?

"cup" is the more common of the two: it sits at frequency rank #805 in our English list, against #39,729 for "CD4". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Useful next steps

You've compared "CD4" and "cup". Here's where to go from here.

Full dictionary entry for "CD4" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "cup" - compare definitions side by side with the headword page. Word entry
This pair ranks #266,683 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"CD4" and "cup" also get mixed up with nearby pairs, the highest-scored neighbour is "CD4 vs CGT". Nearby pair

Confusion rank #266,683 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.