er vs ESA, What's the Difference?

Which to use

“er” is an intj and “ESA” is a name - they look or sound alike but fill different roles in a sentence.

#4,756
“er” frequency rank: #20,108
“ESA” frequency rank: 24864
confusion score

Side-by-Side Comparison

Feature	er	ESA
Definition	Said when hesitating in speech.	Initialism of European Space Agency.

Letter map: er vs ESA

Shared letters muted; letters that set er and ESA apart highlighted. Shared run: 1.

2 ch

3 ch

ESA

Role in the sentence - er and ESA

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: er is anintj and ESAaname. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 24864, derived from the frequency rank of both members and their visual similarity.

er is recorded at frequency rank #4,756, classified as anintj, pronounced /ɜː/. ESA is at rank #20,108, tagged as aname.

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 24864, this pair ranks #398,755 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of er vs ESA

Shared letters: e. Private to "er": r. Private to "ESA": as.

"er" · 2 letters · shape VC · "ESA" · 3 letters · shape VCV

Frequently Asked Questions

Is swapping "er" for "ESA" ever safe?

No - they are not even the same part of speech. "er" is an intj and "ESA" a name, so a sentence built for one is usually ungrammatical with the other.

Frequency check: "er" vs "ESA" - which ranks higher?

"er" is the more common of the two: it sits at frequency rank #4,756 in our English list, against #20,108 for "ESA". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

You've compared "er" and "ESA". Here's where to go from here.

Full dictionary entry for "er" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "ESA" - compare definitions side by side with the headword page. Word entry
This pair ranks #398,755 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"er" and "ESA" also get mixed up with nearby pairs, the highest-scored neighbour is "Eri vs ESA". Nearby pair

Confusion rank #398,755 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.