theresvsthermosWhich spelling fits?

Quick tell: theres is a contraction, thermos is a noun, so they fill different roles in a sentence.

Which to use

“theres” is a contraction and “thermos” is a noun - they look or sound alike but fill different roles in a sentence.

#8,365
“theres” frequency rank
#44,527
“thermos” frequency rank
52892
confusion score

Side-by-Side Comparison

Feature theres thermos
Definition There is; there's. A bottle, flask or similar vessel having a vacuum between its inner and outer silvered walls; designed to maintain the temperature of its contents

Letter map: theres vs thermos

Shared letters muted; letters that set theres and thermos apart highlighted. Shared run: 5. theres runs 6 letters (CCVCVC) against thermos's 7 (CCVCCVC) - the length gap alone is often enough to separate them once you know to check it.

6 ch
theres
7 ch
thermos

Part-of-speech tell for theres / thermos

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: theres is acontraction and thermosanoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 52892, derived from the frequency rank of both members and their visual similarity.

theres is recorded at frequency rank #8,365, classified as acontraction. thermos is at rank #44,527, tagged as anoun, pronounced /ˈθɜː.mɒs/.

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 52892, this pair ranks #153,321 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of theres vs thermos

Shared letters: ehrst. Private to "theres": -. Private to "thermos": mo.

"theres" · 6 letters · shape CCVCVC  ·  "thermos" · 7 letters · shape CCVCCVC

Known mistypes of this pair

  • theres ← hteres · tehres · theers · theress · therres · therse · thheres · ttheres
  • thermos ← htermos · tehrmos · themros · thermmos · thermoss · thermso · theroms · therrmos

Frequently Asked Questions

Is swapping "theres" for "thermos" ever safe?
No - they are not even the same part of speech. "theres" is a contraction and "thermos" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "theres" or "thermos"?
"theres" is the more common of the two: it sits at frequency rank #8,365 in our English list, against #44,527 for "thermos". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

You've compared "theres" and "thermos". Here's where to go from here.

  • Full dictionary entry for "theres" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "thermos" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #153,321 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "theres" and "thermos" also get mixed up with nearby pairs, the highest-scored neighbour is "thereon vs thermos". 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 #153,321 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