sthvssumWhat's the difference?

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

Which to use

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

#40,035
“sth” frequency rank
#4,050
“sum” frequency rank
44085
confusion score

Side-by-Side Comparison

Feature sth sum
Definition Abbreviation of something. A quantity obtained by addition or aggregation.

Where the spellings diverge

Shared letters are muted; the letters that actually set sth and sum apart are highlighted. They share 1 letter in sequence, which is exactly why the eye skips the difference.

3 ch
sth
3 ch
sum

Spelling & Dictionary Insight

sth and sum form a confusable pair in the English index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They share most of their letters but differ in 2 positions - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 44085, derived from the frequency rank of both members and their visual similarity.

sth is recorded at frequency rank #40,035, classified as apron. sum is at rank #4,050, tagged as anoun, pronounced /sʌm/.

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 44085, this pair ranks #233,847 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Frequency comparison

sth#40,035
sum#4,050

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "sth" and "sum" be used interchangeably?
No, "sth" and "sum" have distinct meanings and cannot be swapped without changing the meaning of a sentence. Understanding the specific definition and context for each word is essential for correct usage.

Remembering sth vs sum

The fastest way to pick the right one every time.

  • Check the role first: if you need a pronoun, it's “sth”; for a noun, it's “sum”.
  • See each word in full, definition, IPA, etymology and its other confusables. Full “sth” entry
  • Browse more pairs most likely to be confused. Most confusable

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

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list