secondaryvssecondlyWhat's the difference?

Quick tell: secondary is a adjective, secondly is an adverb, so they fill different roles in a sentence.

Which to use

“secondary” is an adjective and “secondly” is an adverb - they look or sound alike but fill different roles in a sentence.

#2,861
“secondary” frequency rank
#8,981
“secondly” frequency rank
11842
confusion score

Side-by-Side Comparison

Feature secondary secondly
Definition Next in order to the first or primary; of second place in origin, rank, etc. In the second place.

Where the spellings diverge

Shared letters are muted; the letters that actually set secondary and secondly apart are highlighted. They share 7 letters in sequence, which is exactly why the eye skips the difference.

9 ch
secondary
8 ch
secondly

Spelling & Dictionary Insight

secondary and secondly form a confusable pair in the English index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They differ by 1 letter(s) in length - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 11842, derived from the frequency rank of both members and their visual similarity.

secondary is recorded at frequency rank #2,861, classified as anadj, pronounced /ˈsɛkənd(ə)ɹɪ/. secondly is at rank #8,981, tagged as anadv, pronounced /ˈsɛk.(ə)ndli/.

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 11842, this pair ranks #484,845 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Frequency comparison

secondary#2,861
secondly#8,981

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "secondary" and "secondly" be used interchangeably?
No, "secondary" and "secondly" 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 secondary vs secondly

The fastest way to pick the right one every time.

  • Check the role first: if you need an adjective, it's “secondary”; for an adverb, it's “secondly”.
  • See each word in full, definition, IPA, etymology and its other confusables. Full “secondary” 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