specvsstemWhich spelling fits?

Which to use

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

#13,245
“spec” frequency rank
#4,336
“stem” frequency rank
17581
confusion score

Side-by-Side Comparison

Feature spec stem
Definition Clipping of specification. The stock of a family; a race or generation of progenitors.

Where the eye mixes spec and stem

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
spec
4 ch
stem

Why the eye confuses spec with stem

A purely visual mix-up. spec (/ˈspɛk/) and stem (/stɛm/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 17581, derived from the frequency rank of both members and their visual similarity.

spec is recorded at frequency rank #13,245, classified as anoun, pronounced /ˈspɛk/. stem is at rank #4,336, tagged as anoun, pronounced /stɛm/.

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 17581, this pair ranks #450,461 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of spec vs stem

Shared letters: es. Private to "spec": cp. Private to "stem": mt.

"spec" · 4 letters · shape CCVC  ·  "stem" · 4 letters · shape CCVC

Known mistypes of this pair

  • specpsec · sepc · spce · specc · sppec · sspec
  • stemsetm · sstem · stemm · stme · sttem · tsem

Frequently Asked Questions

Can "spec" and "stem" be used interchangeably?
No. They are said differently (/ˈspɛk/ versus /stɛm/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "spec" or "stem"?
"stem" is the more common of the two: it sits at frequency rank #4,336 in our English list, against #13,245 for "spec". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "spec" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "stem" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #450,461 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "spec" and "stem" also get mixed up with nearby pairs, the highest-scored neighbour is "sez vs spec". 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 #450,461 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