LEMvslestTell them apart

Quick tell: LEM is a noun, lest is a conjunction, so they fill different roles in a sentence.

Which to use

“LEM” is a noun and “lest” is a conjunction - they look or sound alike but fill different roles in a sentence.

#35,810
“LEM” frequency rank
#14,158
“lest” frequency rank
49968
confusion score

Side-by-Side Comparison

Feature LEM lest
Definition Originally Lunar Excursion Module, latterly Lunar Module. For fear that; that not; in order to prevent something from happening; in case.

Letter map: LEM vs lest

Shared letters muted; letters that set LEM and lest apart highlighted. Shared run: 2.

3 ch
LEM
4 ch
lest

Grammar separator: LEM vs lest

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: LEM is anoun and lestaconjunction. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 49968, derived from the frequency rank of both members and their visual similarity.

LEM is recorded at frequency rank #35,810, classified as anoun. lest is at rank #14,158, tagged as aconj, pronounced /lɛst/.

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 49968, this pair ranks #178,573 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of LEM vs lest

Shared letters: el. Private to "LEM": m. Private to "lest": st.

"LEM" · 3 letters · shape CVC  ·  "lest" · 4 letters · shape CVCC

Known mistypes of this pair

  • lestelst · lesst · lestt · llest · lset

Frequently Asked Questions

Can "LEM" and "lest" be used interchangeably?
No - they are not even the same part of speech. "LEM" is a noun and "lest" a conjunction, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "LEM" vs "lest" - which ranks higher?
"lest" is the more common of the two: it sits at frequency rank #14,158 in our English list, against #35,810 for "LEM". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

You've compared "LEM" and "lest". Here's where to go from here.

  • Full dictionary entry for "LEM" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "lest" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #178,573 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "LEM" and "lest" also get mixed up with nearby pairs, the highest-scored neighbour is "LEM vs LSC". 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 #178,573 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