observationvssumWhich spelling fits?

Quick tell: observation is a noun, sum is a verb, so they fill different roles in a sentence.

Which to use

“observation” is a noun and “sum” is a verb - they look or sound alike but fill different roles in a sentence.

#49,936
“observation” frequency rank
#31,289
“sum” frequency rank
81225
confusion score

Side-by-Side Comparison

Feature observation sum
Definition Beobachtung, Observation, Überwachung 1. Person Singular Indikativ Präsens Aktiv des Verbs esse

Letter map: observation vs sum

Shared letters muted; letters that set observation and sum apart highlighted. Shared run: 1.

11 ch
observation
3 ch
sum

Role in the sentence - observation and sum

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: observation is anoun and sumaverb. On the page they differ by 8 letter(s) in length. Our composite confusion score for this pair is 81225, derived from the frequency rank of both members and their visual similarity.

observation is recorded at frequency rank #49,936, classified as anoun, pronounced […]. sum is at rank #31,289, tagged as averb, pronounced […].

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 81225, this pair ranks #179,941 of 2,006,359 scored German confusable pairs - among the most confusable pairs.

Orthographic DNA of observation vs sum

Shared letters: s. Private to "observation": abeinortv. Private to "sum": mu.

"observation" · 11 letters · shape VCCVCCVCVVC  ·  "sum" · 3 letters · shape CVC

Known mistypes of this pair

  • observationboservation · obbservation · obesrvation · obseravtion · obserrvation · observaiton · observatino · observationn

Frequently Asked Questions

Can "observation" and "sum" be used interchangeably?
No - they are not even the same part of speech. "observation" is a noun and "sum" a verb, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "observation" or "sum"?
"sum" is the more common of the two: it sits at frequency rank #31,289 in our German list, against #49,936 for "observation". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Pair "observation" vs "sum" is on the table, pick a follow-up below.

  • Full dictionary entry for "observation" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sum" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #179,941 of 2,006,359 scored German confusable pairs in this corpus vintage. Corpus statistics
  • "observation" and "sum" also get mixed up with nearby pairs, the highest-scored neighbour is "observation vs puzzles". 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 #179,941 of 2,006,359 scored German pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list