close vs CMOS, What's the Difference?

Which to use

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

#431
“close” frequency rank: #31,112
“CMOS” frequency rank: 31543
confusion score

Side-by-Side Comparison

Feature	close	CMOS
Definition	To remove or block an opening, gap or passage through.	Initialism of complementary metal–oxide–semiconductor.

Where the eye mixes close and CMOS

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

5 ch

4 ch

CMOS

Visual trap between close and CMOS

These two trip readers on the page rather than in the ear: close is /kləʊz/ while CMOS is /ˈsiːmɒs/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 31543, derived from the frequency rank of both members and their visual similarity.

close is recorded at frequency rank #431, classified as averb, pronounced /kləʊz/. CMOS is at rank #31,112, tagged as anoun, pronounced /ˈsiːmɒs/.

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 31543, this pair ranks #345,213 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of close vs CMOS

Shared letters: cos. Private to "close": el. Private to "CMOS": m.

"close" · 5 letters · shape CCVCV · "CMOS" · 4 letters · shape CCVC

Known mistypes of this pair

close ← cclose · cllose · cloes · closse · clsoe · colse · lcose
CMOS ← ccmos · cmmos · cmoss · cmso · mcos

Frequently Asked Questions

Can "close" and "CMOS" be used interchangeably?

No - they are not even the same part of speech. "close" is a verb and "CMOS" a noun, so a sentence built for one is usually ungrammatical with the other.

Frequency check: "close" vs "CMOS" - which ranks higher?

"close" is the more common of the two: it sits at frequency rank #431 in our English list, against #31,112 for "CMOS". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

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

Full dictionary entry for "close" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "CMOS" - compare definitions side by side with the headword page. Word entry
This pair ranks #345,213 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"close" and "CMOS" also get mixed up with nearby pairs, the highest-scored neighbour is "CMOS vs coms". 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 #345,213 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.