modularvsmodulusTell them apart

Quick tell: modular is a adjective, modulus is a noun, so they fill different roles in a sentence.

Which to use

“modular” is an adjective and “modulus” is a noun - they look or sound alike but fill different roles in a sentence.

#14,795
“modular” frequency rank
#39,433
“modulus” frequency rank
54228
confusion score

Side-by-Side Comparison

Feature modular modulus
Definition Consisting of separate modules; especially where each module performs or fulfills some specified function and could be replaced by a similar module for the same function, independently of the other modules. The base with respect to which a congruence is computed.

Where the eye mixes modular and modulus

Muted = shared; highlighted = the visual trap. They share 5 letters in sequence.

7 ch
modular
7 ch
modulus

Visual trap between modular and modulus

These two trip readers on the page rather than in the ear: modular is /ˈmɒdjʊlə(ɹ)/ while modulus is /ˈmɒdjʊləs/. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 54228, derived from the frequency rank of both members and their visual similarity.

modular is recorded at frequency rank #14,795, classified as anadj, pronounced /ˈmɒdjʊlə(ɹ)/. modulus is at rank #39,433, tagged as anoun, pronounced /ˈmɒdjʊləs/.

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 54228, this pair ranks #142,726 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of modular vs modulus

Shared letters: dlmou. Private to "modular": ar. Private to "modulus": s.

"modular" · 7 letters · shape CVCVCVC  ·  "modulus" · 7 letters · shape CVCVCVC

Known mistypes of this pair

  • modularmdoular · mmodular · moddular · modluar · modualr · modularr · modullar · modulra
  • modulusmdoulus · mmodulus · moddulus · modluus · modullus · modulsu · moduluss · moduuls

Frequently Asked Questions

Can "modular" and "modulus" be used interchangeably?
No - they are not even the same part of speech. "modular" is an adjective and "modulus" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "modular" vs "modulus" - which ranks higher?
"modular" is the more common of the two: it sits at frequency rank #14,795 in our English list, against #39,433 for "modulus". 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 "modular" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "modulus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #142,726 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "modular" and "modulus" also get mixed up with nearby pairs, the highest-scored neighbour is "modulus vs modus". 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 #142,726 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